4" lift is all you need for 37's. 3" with the correct bump stops will also work.
If you have an auto the factory drive shaft slip joint boot will invariably get ripped up on the side of the trans pan. The boots at the cv's may also fail over time. An aftermarket shaft will be a lot more picky about pinion angle, but will negate the above issues. Both can fail given abuse, but an aftermarket shaft is a lot easier to re-build in the field.