The key here is that F on VX is actually real first class, not the "first class" that a lot of legacy airlines try to pass off as F. Just because they are labelled the same does not mean that they are the same. Your choices are, pay for something good, or get crap for free.

1. not just exit row seats.
2. free drinks as well as free food.

As Gold you get some free lounge passes at LAX. You also get free lounge access with some of their partners.

You are equating Economy Plus with MCS and UA F with VX F. That's just not a fair comparison.

UA flies a lot of planes. I looked at a short-haul flight that I fly often (SFO-LAS), and compared.

In F, both give you 21 inch wide seats. But VX gives you 55 in of pitch, while UA gives you 38 in. They are taking away your legroom by cramming a lot more seats into the same amount of space.

Comparing Premium Economy on UA to MCS on VX, you get an extra half-inch of seat width on VX (17.7 vs 17.2) and you get 38 in of pitch on VX vs 35 on UA. So in other words, the legroom in VX MCS is the same as the legroom in UA F. And on VX MCS you get free food and drinks. You just can't compare the two products. VX gives you a wider seat with more legroom and free food and drinks. It's not even remotely close. MCS is closer to UA F than it is to UA premium economy.

Just because an airline decides to label a class F, it doesn't mean that it's comparable to other F products. I don't consider 38 in of pitch to be a real F product. When I fly F on VX, I recline all the way and use up all of that space as I relax and sip my drink. If VX was willing to lower their standards to match UA, they could cram an extra row of F seats into the same amount of space (ie, 3 rows instead of 2). But they aren't willing to do that. That's why you have to pay for it -- it's actually worth paying for.

Sure you can. VX is better than UA.

I agree that overall VX is better than UA. That is a no-brainer. But the elite status on UA gets you a lot more than it does on VX. The odds that you sit in a bad coach seat (and VX's regular coach seats are just as bad as UA's) are much lower as a UA elite than as a VX elite. Your odds of getting some kind of upgrade, be it a better coach seat or an upgrade to a higher cabin, are better.

I agree F on VX is much better than F on UA. But if you can never get into it, what does it matter? On the routes I fly, it is very rare (less than one of 10 flights) that I can buy an upgrade into F, even with the 6 hour advantage of Elevate gold, and similarly rare to get an upgrade into MCS where something other than a middle seat is available. On UA I can get a window or aisle seat in Economy Plus just about every time as long as I'm not buying my ticket the day or two before the flight. This is a big difference.

The other point I disagree on is the difference between MCS and Economy Plus. Both are much better than a regular coach seat; the difference between them is much smaller for me than the difference between either one and a regular coach seat.

I agree with that because of the legroom. The main point here is that VX MCS has the same legroom as UA F. Furthermore, the free food and drinks are a significant bonus. My point is just that is is closer to UA F than UA Premium Economy, so free upgrades to MCS are worth a lot. The only thing that you are missing for UA F is the seat width (and they are still wider than UA Premium Economy)

Also, with status, you can pick the front EE row, which has the same legroom as MCS, but doesn't recline (which is why they are MC and not MCS seats). There isa $30 fee to select that seat at booking time, so they are almost always available (even the windows). But you don't have to pay the fee if you have status. So if you want a cheap window seat with legroom, that is always an option.

Personally, I just buy F outright (not upgrades). I find that with the points that I get (10 pts/$ for being gold) it's really not worth it to try to save a few dollars by hoping to be able to buy an upgrade (since you don't get any pts on the upgrade fee). The extra points often offset the potential savings, and you are guaranteed to get the sear. I can usually get the deepest-discount F fares so they really aren't very expensive (I fly mostly short-hauls; I realize that F is much more expensive for transcontinental flights)

If you could guarantee that you wouldn't end up in a middle seat, then I might agree with you. But most of the time an MCS upgrade takes me from a window or aisle to a middle seat, negating much of the value of the upgrade. That would never happen on a legacy airline because there are no middle seats in F.

Unfortunately on BOS-SFO the one-way F fares are in the range of $1600 (discounted) to $2200 (refundable), with coach in the $250 range and MCS around $700. MCS is not worth $450 if you can get the exit row in front of it (IMHO), and the premium for F is very large (well over $1000 each way).

Agree with others that VX MCS is closer to UA Domestic First than E+. The seat pitch is identical, it's just 3" of extra width in UA First. I already view UA First as "E+ with food and alcohol" anyway (and I don't drink much). I'd rather fly VX MCS over UA First as long as my neighbor isn't portly.

I was kind of surprised by this, but when I checked the prices, the cheapest SFO-BOS F seat I could find was $1500, and most were more.

The reason this surprised me is when I was looking a different transcon flight (SFO-FLL) it was possible to get F seats for $800. In this case the difference between booking F and booking MC and buying an upgrade is minimal (since the upgrade would be $400) and mostly offset by the fact that you don't get points for the upgrade fee (10 pts per $ = 22% back in points)

I wonder why the SFO-BOS flight is so much more expensive. I assume that there must be higher demand and/or less competition for that route?

There are a bunch of venture capital firms, biotech companies, and web companies with very senior people who fly back and forth regularly BOS-SFO. VX has only 16 seats/day of a product that is much better than the alternatives (UA F or JetBlue Even More Space), and with this group, price doesn't matter. So they (VX) are in the fortunate position of being able to charge what the market will bear, which is quite high. If they had more flights or more seats/flight, I'd guess the price would come down (and historically when they had 3 flights/day, it was lower).

I bear them no ill will for these prices; if that's what people will pay, the more power to them. But as someone buying somewhat cheaper seats, it limits the value of Silver for me.

That seems like a fair assessment. I did notice that if you were willing to take a connecting flight, you could get F seats for $1000 to $1100.

One of the great things about flying F is the people that you meet. It sounds like that BOS-SFO flight is a great place to meet people and maybe line yourself up for a career upgrade (only half kidding here)

Just curious, does the Gold free space-available MCS upgrade benefit also apply to award redemption MC tickets?

No, it does not.