Look Mum, New Bike (Look 464 build)

Having done a couple of longer rides on my alu tarck bike in the last couple of weeks, I would definitely advise making sure there's enough left in your budget for a pair of bib shorts with some very comfortable padding.

HTFU. I raced 50s on the Koga with 20c tyres at 120psi, wasn't that big a deal. With 25s pumped to optimise ride rather than minimise rolling resistance and road bars allowing changes of position, a track frame will be fine for longer rides. I'd be surprised if the 464 was stiffer than Look's stiff versions of their road race frames.