A larger back housing will spool up slower, won't get as hot and can run high boost as won't stall dew 2 the fact they can flow more air.
If a t34 and a t35 are the same y didn't they just call them t34s? A t34 is a modified turbo using components, where a t35 is a product that has been manufactured and sold.
But as I said before, might be wrong!!