Drop in Tub Sweat or compression

My DH is ready to connect the plumbing for our drop in tub. Should he sweat all the fittings or use comression. On the filler spout he would have to sweat the copper to the brass after install sense there is no room to turn the brass with the copper if its done before hand. He says he will be upside down looking up to do that connection. The feed into the hot/cold valves does not accept a 1/2" copper pipe. They are the same valves supplied for our sinks which we used flexible tubbing to attach to the supply valve. So it looks like the vendor expects you to use compression fittings everywhere but once the tub is in we will not be able to see any leaks, etc.

What do you normally do?

Thanks