I used this bag on a recent trip that took me from the Middle East to Paris to Georgia (the country) and back again. The bag is solidly built and can handle a huge load of gear. The wheels can handle rough terrain and the handle is tough and easy to grip. The shoulder/waist pad assembly is a little bulky, but very comfortable for extended rucking.
There are only two downsides to this bag. The first is weight- be prepared to pay for having a heavy bag if your airline has a 50lb/23kg weight limit. Everything that makes this bag tough also makes it weigh more. Personally, I don't mind the extra weight- I look for durability and this bag has it. The second problem has been mentioned before. The main zipper is large and rugged- able to handle a lot of abuse. The smaller zipper that connects the outer compression straps, however, is another story entirely. I have already had one side blow out and was able to get it fixed by a local seamstress. Not a dealbreaker, but important to understand and prepare for.
Overall, an excellent bag and a purchase I do not regret. I beat the crap out of this bag and it has been up to the task. The inside toiletry bag was excellent- I don't worry about trying to attach it inside (it is difficult but also unnecessary). Use the small bag as a carryon (there's a clever cover that zips into place on the main bag when the smaller one is detached) and have a little extra money to cover the extra weight and you'll be fine.