Realtick has it.
It seems to me that you need your front-end interface to have access to Arca's itch feed (depth of book).
Redi-plus is just a front-end to route orders to the ECN's, Nasdaq and the Exchanges.
Have your system folks set-up a program to measure acknowledgement times. This is what some sophisticated shops use to measure speed.
Brut is fast, economical and reliable! A number of traders feel the same way and have set-up Brut as the default destination on their box.
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