Daryl it really depends on what you want out of it. Best bang for buck is going to be the nistune.
I honestly think you need to sit down and work out exactly what your plan is.
Otherwise you are going to have all these mismatched parts and no idea of what you actually want.
Set yourself a goal and then research how to get there.
Are you looking to get to that power goal the easy and cheap way or the safer and more expensive way.
I made the mistake of focusing purely on power and neglecting handling, braking and general maintenance.
This left me with a 250kw car that feels like shit to drive these days.