The SiT is a class A device with the transconductance qualities of a triode... so I would not define it as ’solid state" sound.
Now, the other amps... Maggies. I got 1.7s and 12s. Also got clone F4, F5, A2 and mono A5s. ( Plus a set of SiT transistors for the next amp). And an ARC D70-II.
My preamp is a tube CJ that can swing 20V.
The SiT / Maggie combo will sound great at lower levels, but truly, they come alive with lots of power. Just like my F4 and F5 sound extremely good, when I plug in the A2 the music simply comes alive, not just the "sound of Aleph" but also the reserves of power: it sounds like an additional deep down octave came on line and the dynamic range snaps to life.
THAT, IMHO is the big difference: the lower power amps will drive the Maggies to good sound levels but you lack the dynamic range. Adding more, clean, power, lets you play at the same level but now you have dynamic range... it just sounds "louder" because the bass suddenly appears, also, the treble is cleaner as temporary peaks will not drive the amp into the harshness of clipping.
BTW, in my main system I’m currently driving the 1.7/A2 and Elac Unifi B52/F4. The F4 is fantastic (really needs those 20V from the preamp)... but ultimately the Maggies with 200wpc are the more satisfying sound - whole, top to bottom.
My advice to the OP:
(1) Your preamp should swing 20V.
(2) Get a pair of used Aleph 2s for the Maggies ( clones are fine ). If SS, it must be a class A amp... or perhaps a used ARC D115-II, VT100, etc... must have over 100 watts!
(3) Find a pair of efficient speakers for the SiT and post that here... because I’m also looking for that.
IMHO, the SiT and Maggies are a system for the brain... but sometimes, you need to feed your heart.