A500/A518 to Gen-III

Guys, my Gen III 5.7 arrives next week. I had steered away from the 518 route and was staying with the 904 when I was going with a Magnum build. But, I’m curious now, anybody have an opinion on the performance of the A518 vs. 904 when behind a 5.7? Is there a noticeable power loss as a result of the OD? I had read, mind you on the Internet, the 518 would choke your HP and advised to “stay with the 727” . Mine won’t be a “daily” driver, but I do intend to drive it regularly. And honestly since I won’t be frequenting the track, I would forgo an 1/8th of a sec worth of HP for the flexibility of driving where/when/how I want.

Any truth to this or do the benefits outweigh the mods and minor decrease in HP?

Pics?