I bought this as a large daysack to replace an old Karrimor which always gave me a sweaty back.
Bought for £48, it's great value for money. Loads of pockets, and loads of room. The main sack is shallow front to back, but if you want a gap between the sack and your back, and you don't want the sack to make you lean forward because the weight is too far back, then there's no avoiding it.
Straps all adjust well and are comfortable. There are extra adjustments to raise and lower the overall sack position, and the chest strap. It seems very well made. The freeflow system does keep your back a lot cooler. The rain cover is a bonus.
Overall, and excellent sack with lots of nifty design features.