I suggest driving a post 350whp GC. 600? HA.I would most likely go for the EG33 because there are a lot of them readily available for not much money.
The power would be sweet but I'm not looking for 600whp, this car is going to be my DD, thats why with the eg33 I was thinking like 350-400 even though thats more than enough but hey. I'm not sure though I think it would be more cost effective and make more sense to go with the ej257. I could always do a 300whp N/A build with the EG lol
Your struggle is to find a drivetrain solution to suit your big power dreams.
Get out the wallet for 250+whp on an eg33