very little tbh mate.
After the cat, there's very little restriction, so not much in the way of performance gains to be had. It'll make a bit more noise tho
, but I'd wait for the full TBE.
I wouldn't let either sway you from a re-map tho. Once the TBE is on, the map could be adjusted to suit
With K03, Revo Stg1 and an ITG intake, my car made 255bhp on JKM's RR. The intake made about a 15bhp difference on the same day, on the same rollers.
Never got to do the same test with TBE tho, but at the last JKM RR day, various K03 cars with map, intake & TBE were pulling 260bhp - 270bhp.