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AO Silver Member
Join Date: Dec 2013
Location: United Kingdom
It really depends on availablity of any particular item. Often patent parts can be as good as OEMs, but this also comes down to, to a certain degree, how old your car is and its worth and, to a lesser extent, finances.
As regards performance gains by modding, that'll depend on size of engine. So, for instance, if you want to remap a 1.6 Alfa, the benefits will probably be minimal in comparison to a 3.2 GTA.
Personally speaking, I have no interest in modding, remapping or 'souping up' my 1.8TS. Originality has a distinct charm.
If the shoes don't fit, change the horse.