I use one for lighter trips and it's fine. It carries a fair bit and I can even squeeze a 15" laptop in the rear compartment. Despite 18 months of abuse, it still looks pretty much as it did the day I got it with no fraying bits or failed stitching. It also has the benefit of not looking too conspicuous if you're heading into potential unfriendly areas.
Bob
1Dx2 (2), 5DSR, 1Ds3, 1D4, 5D2(590nm), 5D2(720nm) EF600 EF400 EF300-II EF300 EF200 EF200-II EF180L EF135L EF100 EF85-II EF50L TS-E17/4 TS-E24L-II TS-E45 TS-E90 MP-E65 EF70-200-II EF24-70/2.8-II EF16-35/4 EF8-15/4 EF11-24/4 Zeiss 15/2.8 21/2.8 25/2 28/2 35/1.4 35/2 50/2 85/1.4 100/2 135/2 T/C's L-SC & a WIFE!