Chris
Bad cop
My dad is ~17 stone and about 6'2" and he fitted (wedged) into my Recaro's perfectly fine the other weekend when we took a jolly to Brands Hatch. I'm sure you'll be absolutely fine. You may want to get some resistors to sort out the airbag light when you fit the new seats. Unless you know someone who can get rid of them with software?
Yes getting people in them isn't the problem, it's how to get them out!!!
Nice one Simon, not afraid of throwing some £££ at he beast