Re: GM 7 blade fan vs Metal flexalite fan. Whats the better buy
No. But they would likely carry the thermostatic fan clutch that you need with the GM fan; it cannot be used without the clutch. And the clutch is another $50 or so.
If you want to run a flex fan because you don't want to spend $130 or so on the GM fan and clutch, that's okay. Just measure and get what you need, and make sure you get a fan spacer to properly position the fan in the shroud (you can't just bolt the $26 flex fan to the water pump pulley and call it good...).
69 'vert project big block/TKO 600 RR
68 'vert driver RS clone -- gone!