I am running the wire for a 40 amp 240V spa that recommends the use of #8AWG THHN wire. The overall run from the main panel to the control panel on the spa is 75'. Due to cost and availability I am considering using a 50 amp 240V spa panel (GFCI disconnect). I would still be using a 40 amp double pole breaker in the main panel and #8AWG wire. Would this configuration be okay? I figure the 40 amp breaker in the main panel would protect the #8 wire and the 50 amp GFCI disconnect would protect against fault? Any help is appreciated!