Jonny T, re your better fill on a Stop, it happens during the nano second between your order entering and getting filled and a bigger market order going in the other way. The size order takes out bids or offers to it's limit level. Unlucky if he's the same way and gets in first though!
ps. 9 point stop could be whippy.
Craig, I use TWS4 standalone normally, and have only used the web based platform a couple of times. My initial perception (and it's nothing more than that) is that TWS was a little quicker than the web, but not noticably. This was for US shares - haven't traded the ftse future thru the web, only TWS4.