T38 can be mega responsive on a live map easily, I have a T4 (not live mapped) and it's like waiting for a bus for it to make boost. I am planning to get it properly set up oce I have the right transmission to cope with the power. If cost is not an issue then I'd go for the most responsive and modern design of turbo you can get to match the spec. no brainer really, but speak to a well established tuner to find out what would suit it best.