Want ot go for valves amp

Anyone please give me some opinion about this integate amp that i have listed below, Which one do you think the best valve integate.
I am just about to change my system into valve. The pre/power I have got at the moment is Avi s2000p and alchemist forsetti signature power. and My speaker is Zingali overture 2s(91db).

- unison research simply 4
- audio note soro se
- tube technology unisis
- Unison research 845(the most expensive one).

I know the 845 might be the best one but i would like to know some opinion about others as well like simply 4 or unisis. Or should i go for valve pre/power but this will costs me much more expensive. I may get the new power first then following by the preamp later.

For your first foray into tubes, a used Cary SLI-80 or Manley Stingray is a cool choice. Great audio and awesome looks on both(no one asks you if they are solid state or tubes!!!!!!!!). For a hybrid, Unison Research Unico. If you are wanting the total single ended triode "experience" the DECWARE Zen integrated is superb!

The ones I have suggested can be bought reasonably on the used market and all of them will have a higher resale should you desire to exit for another choice.

Best wishes.........GH
Goo for Unison 845 or Simply 4 !!!
After all Italian goes with Italian nicely.
I have all Italian comp. and Im werry happy !!!
All the best !!