As a punter, I always prefer AW over agencies. One Thai WG that I have seen and reviewed was £60/hh (now £70/hh) & £120/hh on AW and her agencies rate was £150/hh & no hh booking available. I go for agencies when the WG that I want to see is only available on agency or cheaper on agency.
I'm the opposite. Been punting for over 20 years now and my hit rate with agency girls far exceeds my hit rate with indies/AW girls.
For me using agencies has been a superior experience in almost every way. Comms have been way, way WAY superior with agencies vs AW where it seems most girls can't be arsed to pick up the phone let alone respond AT ALL to messages. The booking process itself is extremely easy, plenty of last minute "I'm feeling horny as fuck and just have to fuck a hottie right now" phonecalls that lead to a great punt 30 minutes/1 hour later (practically impossible via the AW system), but for me, commonplace using agencies.
I've found many great and very reliable regulars using agencies, only 1 using AW.
AW may be generally cheaper, I punt almost exclusively with Thais, so typically pay the standard £150/hr, but that extra £20-£30 for me is absolutely worth the exponential increase in convenience, reliability and professionalism.