Quote from traderTX:
for charts you'll probably want to get a software package, as opposed to anything the brokers could provide. I think ADMIS is the only broker that even has their own software that supports charting of ag spreads (both exchange recognized and custom). Look at DTN, CQG, etc.
What type of spreads are you looking to do? If its an exchange spread (time spread) then you should be able to execute that at any futures broker...just so long as they SPECIALIZE in futures...not just a broker that offers futures.
For inter-market and complex spreads, you'll have to leg those anyway, so excecution platform is more important than the broker.
My recommendation for broker though would be either Advantage Futures (self clearing), Global Futures (through RCG), or if you need more of a "full service" deal, either ADMIS or Man