HowTo? Fixed / Singlespeed conversion from an old bike

I think filling bits off and loosing the original paint job is a shame (and will ultimately be regreted) but they're just bikes.

Agreed!

I just think if you're going to spend the sort of money a +£200 frame will make your build cost, you may as well take the easier option.

I just think conversions can be the easier option, at least if you do want to run a brake. The hassle of respacing a rear axle is pretty minimal, but finding ultra low reach calipers, possibly drilling forks, and then braking on a fork which isn't designed for those forces is probably more hassle, not less.

I should add I've only come to this conclusion recently as I'm building up my first track frame after building and riding several conversions for the past 3 years... Maybe after the first ride I'll be converted against conversions, but at the moment my Samson is more hassle than a road frame by far