This is rather a pointless thing to track. Why would you want to track all existing brokers?
To be able to compare good and bad brokers.
when you scalp you need a fast broker and a low spread.
a slow execution can results in catastrophic results.
you'll suffer requotes, closing a trade is a big problem, even moving the SL/TP is slow. and with an EA which can execute a lot of trades, this become just unmanageable.
I saw execution time of 10 seconds... imagine when the EA open 6 trades on different currencies and try to move the SL of over trades... this takes minutes to be completed!!!
not good at all.
when you trade at the day level its less important.