I want to post a final comment on this topic:
I have had the SR circuit installed in the Film Cap version and in the Stock version of my two SII amps for several weeks. After much comparison ( before and after SR) I can honestly say that prior to the SR install, the Film Cap version seemed to have a better low end and more detail than the stock version. After the SR install the two amps sound nearly identical two me.Film Caps might have better bass but I can't swear to it as my A to B comparison requires break down and set up time, so it's not exactly instantaneous. So, I really don't recommend swapping out the PS caps, I don't really see any advantage, other than the film caps may last longer, but with the amount of work that it required, you could definitely change your electrolytics a lot faster.
I have considered the possibility that the lead length on those film caps is so long that perhaps it is offsetting the advantages of those big caps, so I might shorten those to see if there is improvement. But at this point, I really think that the circuit is so optimized that changing certain parts out for more expensive and less convenient versions yields very little improvement, especially since the SR circuit came along.
Jamie