Quote from jkhek21:
We do offer Ninja Trader as an order execution platform as well as X-Trader.
Quote from Bernard111:
Oh, yes --we alreay know GFETC offers Ninja on the slow and unreliable Pats feed and X_Trader w/ the monthly TT fees with RCG or Penson-GHCO...
http://www.elitetrader.com/vb/showthread.php?s=&threadid=100319
[no affiliation with GF. And I found the vendors post useful.]