I think I can speak here as I have a little experance with this , I currently run a gt3040R on an rb20 a built engine and I spent thousands getting it to flow its great as it boosts pretty early and is fairly powerful car ran an 11.7 at wsid ,while this is great for a track car its not for a streeter as when it comes on boost its wheel speen city even with perrilli P zero's and on low boost ,low boost it makes 240rwkw but the way it comes on is a rush of power from 3900rpm to 5100rpm it goes from about 80rwkw to 288rwkw so in 1200rpm it makes 208rwkw thats a lot of power for the rear wheels to hold
I would tend to agree with Roy and URAS ,from graphs I've seen the tdo6 has a lot more linial power delivery to the garrett turbos as they come on in a rush and the gt3540 would be worse than mine .
I dont drive my car on the street anymore as for one its just too wild and two with the new hoon laws with that sorta power delivery with out r spec tyres there aint gonna be any traction and in front of a cop bye bye car so my engine is coming out the car is going back to stock to be sold of and I've now got a gtr so got better chance of keeping the power to the ground . This is just my opinion but hope it helps
cheers Peter