Which is the best amplication?

Ok I know it has been done before...

I have narrowed (!) the choice of amplification for my speakers (SF grand piano homes: 90 db and 6 Ohms) to the following. I have not listened to some of these and I plan to buy S/H. Your experience and considered opinions will therefore be greatly appreciated. My room is medium size (25ft/15/10) and I listen to all types of music (classical, soul, jazz, modern rock etc).

There goes:

1. MF A308 integrated
2. MF A3 pre and a308 power
3. Meridian 502 pre/556 or 557 power
4. Belcanto evo2i integrated
5. Naim 102/180 prepower with hicap
6. Lavardin is
7. Krell 300i/300il

I considered the UR unico. It was pretty good at its price range but I thought the SF could do with better. I also considered the Audio Analogue Maestro (which one of our contributors really liked) but it was quite expensive even s/h and I didn't think the high price was justified.

So there it is.

Tks in avance for any considered feedback.