If you get the hx35, they have the split scroll housing so you'll need to make sure you run a paired header or mill out the divider at the turbine inlet. I'm running an hy35 on my Ford 2.3T engine with a little bit of head work and a good cam and have full boost at 3800 rpms. The hy35 is nearly identical to the hx35, main difference is the turbine inlet and also the turbine housing size. With a paired header on the hx35, a lot of Ford 2.3T guys are getting full spool around 3k-3200 rpms so that makes for a much nicer torque curve. The other thing about holsets is they come on like a light switch, I shoot from 5 psi to 25psi in about 500rpms!

Another thing about the hx35 to look at is finding one with a smaller turbine. The typically come in 14, 16 and I believe 20 cm^2 sizes, but you can find 12cm^2 housings and these are the best for quicker spool times. The hy35 I have is a 9cm^2 housing which is comparible to a .63 t3 turbine housing size.

Holsets are great for a cheap turbo that can support massive power, but next time I'm going to go with a turbo more suited for my build. This one is a little too lazy for me. But I did switch from a 60/48 t3 to the holset, lol.