IMHO, for a 2.5L/EJ255 that is a DD and running a 5-speed tranny I would pick either a TD05H-18 8cm or TD05H-20G 8cm. At this point I think the HTA68 (I think that was what the OP was referrring to) is still unproven and IMHO is a better turbo for the 2.0L/EJ205.
The HTA68 uses a TD05 compressor housing and a 7cm exhaust housing, these are really limiting this turbos potential. While a good 18G or 20G uses a true TD06 compressor housing and you can get it with an 8cm exhaust side, this in turn has excellent flow on a 2.5L with very little possiblility of boost creep.
Personally, I run a Blouch TD05H-18G 8cm on my built hybrid (EJ257/2.5L) and for me it is the perfect turbo for DD/autoX, as it has an excellent/very useable powerband.