I know I know it's late on in the evening I am hungry and had too much stella's but to simplify this whole discussion.
pre-facelift = Norfolk tractor / Sunday leftovers
facelift = 155mph sports car / looks longer 'cause it's lower
modified pre-facelift = facelift
modified facelift = 156mph sports car
just get a facelift to short cut a shed load of pain, and if you are thinking about modifying your TT the first thing you should buy is a WIDEBAND O2 Sensor from a facelift TT as that is the minimum requirement to re-map your car. also you can then use a EGT Sensor to ensure you are not cracking your turbo getting more power out of it.
When I started overclocking computers it was a dark secretive world of sneakily updating things which had not been locked down in a bios, then a motherboard manufacturer took away the sneakiness and published and encouraged the bits and pieces - you need to consider the facelift of a 225 BAM TT, likewise the AMK / BAM S3 an invitation to "have a go" - forget about the pre-facelift TT (APY) or S3 (APY) to get the most out of it - although they will probably out-live the Facelift versions; as me and my 'elk/type? would have blown them all up