I recently made Diamond Plus and am enjoying the perks that come with it already. I didn't get the pack in the mail yet, so can't tell you what it contains, but benefits I've experienced are as follows:

On arrival at ICN, I approached the premium check-in counters and mentioned I was Diamond Plus (even when flying in Y) and was escorted up to the F counter without any waiting, even though there were a number of people in the C line, and lots in Y and the other lines. Without asking I was given the F lounge invite, and I hadn't made any prior seating assignment. I was asked if I wanted a front bulkhead seat but declined. I asked for a seat where the seat next to me would be blocked, and was told fine. I can't think of this ever happening before on OZ. They'll typically say the seat next to me isn't taken, but say they can't guarantee it won't be taken later. No such disclaimer this time.

First class lounge at ICN. This is one of the main reasons for getting Diamond Plus for me. The F lounge probably isn't the best in the world, but it's pretty good for me. Always a good selection of excellent hot food dishes, sushi, great fresh fruits, dim sum, haagen das ice cream bars and cups, a nice selection of nuts, including macadamias, various desserts. I'm sure I forgot plenty on that list. Unlike the C lounge, hot food and everything else seems to be constantly replenished at any time of the day. The drink selection is a definite improvement over the C lounge. I opted for some of the bottled fruit juices not present in the C lounge and was also pleasantly surprised that all the drinks were properly chilled, unlike the C lounge where they're midly chilled at best. One negative was that I decided to have a Haagen Das bar and when biting into it it spurted liquid out being it wasn't properly frozen. I then opted for a ice cream cup instead and it was fine, so perhaps someone left the ice cream bars out before stocking the freezer. Not good for premium ice cream to be melted and then refrozen. I've visited the F lounge a few times and this one time was the only time there was a problem with the ice cream.

I needed a shower and the attendant told me to wait a bit. She came back a minute or two later and asked me to follow her and mentioned she ran the water until it was hot for me. Not really necessary, but certainly a nice touch. As ORDnHKG mentioned in one of his posts, the shower only has the same amenities as the C lounge, which is a slight letdown. The showers are though bigger and have a mat in front of the stall for drying off your feet with...a nice touch missing from the C lounge showers.

Once I was in the F lounge and there were only I think two other people, another time maybe 5 or 6, and the last time about 10 or 12. Never even close to being too many people for the seats, food, staff, or service. Overall, I am very pleased with the F lounge.

I decided to leave the lounge shortly before boarding time as my gate was at the far end. The attendant mentioned my flight wasn't boarding yet and she would call me when it was, but I said that was fine as I wanted to look around a bit. Nice that they remember who I am and my flight number, even though I'm only in the F lounge due to status and not actually flying F.

No special attention when boarding (beyond *G priority boarding), but once seated I noticed one flight attendant motion at another flight attendant and then towards my seat. The other flight attendant promptly came up to me and greeted me and asked me to let her know if I needed anything. She then quickly returned with slippers and other items normally given out in C (I was in Y). The in-flight manager came by a few minutes later and personally greeted me and also asked me to let her know if I needed anything at all. In general the flight attendants seemed to be extra attentive to me. I never asked, but I'm sure it was because I'm Diamond Plus. I declined the meal service, being I already ate way too much in the F lounge, so don't know if they would have done anything special for me if I had, though doubt it. I did ask for some water and juice a few times and was always brought it right away.

On a return flight, I approached the business class check-in lines. A staff member asked me if I was business class, and I said I was Diamond Plus and she immediately mentioned to the manager that I was Diamond Plus and the manager called me there directly and handled my check-in. I was told that Y was full / overbooked and that I would be the first on the list to be upgraded and to check at that gate for my likely upgrade, which did happen. Very satisfied with this also. Being I doubt I'll be competing with other Diamond Plus members for a while, and being there's not likely many Platinum members, I can be assured of upgrades on just about any flights where my cabin is overbooked. ^^^

As I mentioned in another thread, I recently called OZ about reserving a meal in C for an upcoming flight. After the agent took my Asiana Club number, she asked me to hold on while she transferred me to a VIP line. I never heard of this being a feature of Diamond Plus, but assume I was transferred due to my status. I was preoccupied with getting my meal reserved though, and forgot to get the VIP number for next time.

Of course I get the 15% mileage bonus for all OZ flights, as advertised in the Asiana Club rules.

One weird thing with the OZ website. Everything seemed to work fine when logging into my Asiana Club account while I was Silver, Gold, Diamond, and initially Diamond Plus (before the status was officially recognized even though the mileage was over the threshold). Once Diamond Plus was recognized, the status changes to Magic Miles, which is the OZ program for children. An obvious bug with their website, but if I log into the Korean version, it properly indicates Diamond Plus. Some other funky business with the English version about miles needed for next level (Platinum). I think when I was at Diamond level, it was indicating miles needed for Platinum, not Diamond Plus, and now it indicates a negative number of miles needed for the next level, probably because it's confused with me being a Magic Miles member. Anyways, for anyone reaching Diamond Plus, don't worry if you see this as the OZ computers still all recognize you properly as Diamond Plus, not Magic Miles.

So my overall impression of my so far short experience as Diamond Plus is that it was very well worth putting my miles into OZ for the perks it gives, especially being that the majority of my current transpac flights and flights within Asia are on OZ. If not flying on OZ, I don't see any real benefit of it though beyond regular Diamond.

I've got three trips this month alone to experience the F lounge and the other Diamond Plus perks, which hopefully will continue to be just as good as what I've experienced so far. I'll report back with any new experiences and also let everyone know what's in the Diamond Plus pack once I get it. I really wish more airlines would offer this level of service for their super elites. I realize some do and some do even more than OZ does, but having flown lots and lots of TG flights in years past and being their top-tier (only * Gold), I never felt I was given any preferential treatment at all beyond the standard gold benefits they advertise. Due to Diamond Plus, OZ has made me a very satisfied customer and I will strive to use them for all flights where possible.