The car it is going in is irrelevant.
I always ask what poweer you want to have, if only 250 say no point in a T88, for example.
Keeping the smallest turbo that will do the job will both minimise lag and make the car more driveable.
Of course you then get into turbo mods such as different size compressor and turbine housings.
I wanted around 400 eventually so used a .48 turbine, with T34 trim wheel into a T3 machined housing(compressor), with the "usual" 360 bearing ans also step gap seal.
Mine has 150lbft at 1500rpm, but a lot of this is due to de shrouded head, cost of £275 and makes a WORLD of difference.
Ask yourself what sort of power and characterstics you want from the engine, this will decide for you what spec is best.
tabetha