You could buy some (second-hand) TT500 shifters and then sell them on if they don't work. The price is pretty much constant at £20 for a second-hand set.
I think they're good to have as a backup option anyway in case your £90 brifter dies and you have a sportive coming up or something
hmm, i think drops look really cool on this. i'd stick with them personally.
what rear derailleur did you get? and do you have a compatible front derailleur already?