I was able to compare EAR 324(all solid state) and 88PB(a hybrid JET and tubes)in my system. It was rather close in overall tonality, detail retrieval... of course, they have some major differences and my findings are as follows:
1) without internal SUTs(I believe it's the major source of EAR's sonic signature), the MM sections are surprisingly "rather neutral" in tonality(on the contrary, if someone gets used to tube warm of EAR 834), not overly warm or colored(the MM section only), able to reveal the subtle details of different recordings, in respect of transparency(only the MM sections) they goes hand in hand.
2) 88PB is as a whole lower in hum level and very stable for prolonged use as a tubed phono with more than 70dB.
3) 88PB can offer a bit more real-life body of the acoustic instruments with a thin touch of tube warm.
4) 324 is never harsh or thin sounding.
5) 324 is the better choice for someone who owns a lot of MM carts.
6) 88PB is the best if we want to drive the power amp directly from phono with limited budget.
7) PCC88 proves to be much more stable, much quieter(in hybrid design)than ordinary 6DJ8/6922.
I heard ARC PH-7, Rhea & Janus, Audio Valve Sunilda, EAR 912, Nagra VPS, and many others. Each design approach has its strengths and weaknesses and also pretty much depend upon our budget.
I wish this may help...
VBR
Dan