I have. Sorry I didn't reply earlier but I was out with my Urban Disguise 50!
Pros and cons is a bit tough. It either suits you or it doesn't. I use mine either for carrying a fairly small amount of kit or as an extra bag alongside my rucksack if I am taking everything. So, it tends to be used in 2 different configs:
1. Carrying charger, spare batteries, macro flash, macro lens, netbook as an adjunct to my main kit
2. Carrying a small amount of kit - so today, I was out with 1DsII, 100-400, 200/2.8, 1.4x, 2x, flashgun, drink and snacks
Suits what I want just fine.