supercharger or turbocharger for v6?

Neither is inherently more or less harmful than the other.

A turbo at 20psi will be harder on the engine than a supercharger at 7. Conversely, a supercharger at 20psi will be harder than a turbo at 7.

Both at 7psi, a turbo with an inadequate fuel delivery system will hurt way more than a supercharger. Conversely, again, both at 7psi, a supercharger with a poor fuel delivery system will hurt more than a turbo with a good one.

What I'm saying is that neither is inherently harder than the other. If you keep the boost reasonable, make sure you have proper fueling and a good tune, then you'll be okay.

Try to boost too much, or start to detonate or run lean, and it won't matter which you're using, they'll both hurt.

well a properly tuned turbo will make the more power than a proberly tuned super at the same psi. however, there is no manufacturer of turbo kits, so u will have to get a cutom built one. there are some people at 3.8 mustang doin that. dont ever talk about cheap for either of these, cuz neither one ever is

I know of a couple of people who did complete DIY/JY turbo setups for ~$1,000. It definitely can be done cheap, you just have to do your homework and make sure you know what you are doing and what you need.

at the same PSI the turbo is far superiror than the supercharger, but the supercharger is far more tested on the v6 mustang. on a 99 up you are looking at numbers around 300rwhp and 300rwtq with 11psi on a procharger supercharger kit, i would run 7psi daily and 11-12 at the track the KEY to any forced induction set up is THE TUNE TUNE TUNE TUNE and by this i mean DYNO tune at a GOOD GOOD shop and then youwill be fine.