22-24psi and a aggressive tune on -5s will do that.
ya dont need need -10s, they are 450 region.
I think the GTR bolt on market is quite well filled with garrett, and the turbo prices are quite reasonable.
add to the fact its hard to test/swap turbos, and GTR owners mostly choose what works for that reason.
its RB20/RB25 even 25/30 where the most sales and gain is from a business perspective.