For my HT system, I've got an old Arcam 8 integrated amp (2x50 watts RMS) set up to drive my front speakers.
I have an old Arcam AV250 (5x50 watts RMS) integrated amp to drive the rears and centre speakers. The subwoofer is active. This Arcam amp used to drive the five non-bass speakers, then I realised the old integrated amp sitting in the cupboard could be used.
Now I have my G08 analogue L/R outs connected directly to the integrated amp and manually switch to that input (CD) to play music. Then for HT, I switch to the AUX input to receive L/R front audio from the surround decoder. This leaves the surround amp to handle only three speakers. I can also mix and match the subwoofer inputs from the decoder .1 channel for HT, the front channels, or a combination of the two.
To my ears I got a purer L/R sound both for music and for HT using the two-channel integrated. I have two amps now being driven from the one double-wall power socket (three including the subby), but I'd consider what I did a nice upgrade compared to everything going via one five channel amp.
The only hassle is keeping the volume levels the same on both integrated amps, since the 5.1 decoder and Arcam remotes both drive them. A minor pain....luckily that I don't have flatmates who would get totally confused.
Hope that all made sense.