Any one have experience with these?

please dont do that...

http://www.stangnet.com/mustang-forums/806320-these-safe-4-5-lug-wheel-spacer.html

in short, thats a lot of stress on wheel studs, you'd have to find a wheel with a crazy offset (stock wheels wont work, you'll look like a jeep) thats essentially a 2" spacer...

a 5 lug conversion isnt difficult, you can do it in your driveway and it also isnt expensive at all if you find the right parts
 
i dont know anyone running those same ones but i do know a few lightning guys run adaptors to run mustang wheels. but its not something i would do.