Yes, perhaps my analogy was a bit harsh. My primary objection to the GoRuck is in the area of it's suitability for carrying on your back.
First, it is heavy for it's size. Weight is the number one enemy of something you carry on your back. Next, the shoulder straps are not contoured for comfort; there is no sternum strap; there is no hipbelt to transfer weight onto your hips and off your shoulders.
Any pack you look at putting on your back with more than 10lbs. in it needs to address those points. The Goruck simply does not stack up against something like the Osprey Farpoint 40. That it even costs more, makes it even worse.
The RS Appenzell is a day pack Romelle, the basic difference being a 'real' backpack has to have a hipbelt to transfer weight off your shoulders and onto your hips. There is nothing wrong with the Appenzell at all but if you carry more than 10lbs. in it for a few hours you will feel that weight far more than carrying the same load in a pack that transfers weight onto your hips.
I use a 29L Vaude Triset 25+4 pack to carry 5-7kg. (11/15lbs.) It is called a day pack as well due to its size but it has a hip belt. It isn't actually as good a hip belt as on the Osprey Farpoint 40 but as I carry a very light load, it is more than adequate. It does what it needs to do, transfer the weight to the hips. The feature I like best about it and the main reason I chose it over others is the Aeroflex mesh back. Almost invariably when I travel I do some hiking and that air flow back keeps me cool, a big plus. That's something else the RS can't do for you Romelle. But if you only wear it for short periods of time walking from a train station to a hostel/hotel then it isn't such a big deal for you.
http://www.go4awalk.com/product-revi...riset-25+4.php
It is difficult for people to understand just how much of a difference a hipbelt makes when you have a properly fitted pack on your back. You go from knowing you have a pack on your back to almost not knowing it's there. That's with a 5-7kg. load of course, not a 25kg. plus load. Properly fitted, the hip belt should transfer 60% of the weight off your back. So if you were carrying 15lbs/7kg. on your back, it feels like you only have 6lbs./2.8kg. on your shoulders. It is important to know there is a difference between a hipbelt and a waist belt. The hip belt must be sitting on your hips, not above them.
Try an experiment Romelle. Put 6lbs. in your RS bag and see how it feels. Then put 15lbs. in it and see the difference. That's what a hip belt would do for you.
For the average traveller on vacation who wants to sometimes put the bag on their back, the Osprey Farpoint 40 or other similar packs from the major manufacturers is probably the best type of pack to get. My personal choice is more about putting hiking as the first priority.
The Eagle Creek Mountain Valley has some good points armiductor. It has a hip belt; sternum straps; contoured shoulder straps. All the things to look for in a hiking pack. While it has an 'airflow' back, it is not as 'airflow' as a pack which uses a mesh and frame to actually create an airspace between your back and the pack. Not a major issue for most and I do pay a weight penalty, for having that airspace, of over a pound. Finally, it cannot have the shoulder straps zipped away like a travel pack (Osprey Farpoint 40 being the example I've been using here) and so is not airport carousel friendly for the average vacationer. Nevertheless, it's a good pack for many uses.
There is no 'one pack fits all' obviously. The question here is which would best fit the OP's plans for travel in Europe. Again, I would say a travel pack such as the Farpoint 40would be his best choice. That presumes that like most students visiting Europe, he will carry it on his back sometimes from train station to hostel etc. but spend most of his time in cities not carrying it and perhaps occassionally take the odd little hike somewhere.
Filmbuff, I have nothing against GoRuck but frankly I cannot see ANY use for which there is not something better available from some other maker. Their whole 'shtick' seems to be 'special forces, gung ho, bulletproof, for real men, etc.' A lot of nonsense as far as I am concerned. No doubt some are gullible enough to think, when a pack is hurting you to carry it, then you must be a real man.