hi i currently have a tdo5 on my 94wrx what advantages will fitting a vf 43 on to it have? is it worth doing? cheers

 

I guess you mean a VF34 turbo of which has a roller bearing type shaft of which has very good spool up, opposed to a TD05 turbo. Both turbos flow the same amount of air so no real difference in maximum BHP. But a VF34 with decat down pipe would be a better option for a responsive street car.

 

Not wanting to hijack this thread....what about a vf22/28?

 

VF22 turbo is very simular to that of the VF34, where as the VF28 has a smaller compressor wheel so lower top end power with better spool up.
I'd choose a VF22 over a VF28 as it has better air flow further up the rev range, boost is slightly later but what in lacks low down it makes up for higher up the rev range.