Terry, I have experience with one of these amps, close enough I think, to help you on that one. I was, until recently, using a Pass XA-30.5 with my SS M7 monitors. The M7s are somewhat less efficient than the two Salk models you're thinking of. Also, 8 ohm rather than 4 ohm impedance. The 30A integrated basically packages most of the 30.5 in a single chassis. My Salks love the purity of Class-A, but in my case I had to move up to the X-250.5 because the 30.5 wasn't doing the job to my satisfaction in the bass drive department. However, the 30A is a legitimate 'double-down' design so you can expect more power delivery from it into SS8s or or the HT2-TLs. For what it's worth, based on my experience it's iffy.
Since you're focused on integrateds only, have you considered the Luxman L505-uX? Considering pricing for some of the other amps in your list, the 505-uX looks like it's in your price range. I can personally attest to the Luxman-Salk pair-up. It's outstanding, and I'd still be using it with my M7s had I not gone the extreme separates route. Power-wise it's somewhere between the Pass integrated and the Krell integrated, but in my system it had all the bass drive and control I needed. Incidentally, I've also run my M7s with a Krell S-275, the S550i basically packages the (now discontinued) S-275 in a single chassis. Overall, even with it's limitations I much preferred the 30.5 (the Pass sound in general) and I'd go with the Luxman over the S-275 too. Both are smoother - have pretty much a grainless sound - over the precious midrange compared to the Krell.