I'm going to be doing custom software development against an API and I've pretty much decided that I want to use zen-fire, so... My next questions is which brokerage to use that will allow me to use the zen-fire API? Which brokerage to use that offers: 1) <= $2500 minimum to open account 2) <= $1000 ES intraday margin 3) highly competitive commissions (even for low volume) 4) No monthly fees 5) No minimum activity Any recommendations? Related... I recently saw some posts about people signing up with Dorman/Mirus or RCG/Mirus--why would one choose to go with Dorman/RCG as opposed to direct with Mirus? Thanks!