Let me chime in by saying that Fidel runs a very professional operation with his AllSimBaseball.com service.
Our league has been with ASB for close to half a year now and the service has been outstanding. Fidel has always been incredibly responsive to our needs and has bent over backwards to help, including scheduling AIM meetings to go over any questions (and there have been a lot!). You're just not going to get this level of personalized attention focused on OOTP from any other service.
If you've even toyed with the idea of hosting an OOTP league online, this should be your first and last stop.