The best sounding Audio Research Line Stage preamp


I'm in the market for a used Audio Research Line Stage preamp and was wondering if anybody with experience on the following models could help me as to which you might feel would be the best sounding model. I'm after the ARC brand due to it's noted dynamics and clarity. It will be hooked up to a Classe CA-301 power amp and a pair of Magnepan's 3.6R speakers. These are the models I'm considering. The LS2B MkII, LS3B, LS5 MkII, LS12, LS16 MkII, LS22, and the LS25MkII. Thank you for all your help.
uriah
Second the LS5 mk2 with GNSC mod. No dark or muddy, a huge improvement in dynamic. I preferred this pre over the Ref2 mk2 that have got for one week in my room syde by side, in my system and to my taste.
I have also a Supratek Cortese to compare to my Ls5 GNSC mod , both two great sounding pre although being so different.
Please allow me to get some advice about the SS/ LS9. Some stated it was not details due to high frequency roll-off. Some loved it for it warm sound. Thanks in advance.
Haven't heard all those amps, but I am an owner of the Ref 2 Mk I for 5 years and bought it used. Never had a problem. I have been auditioning the Ref 3 and will probably purchase that soon. However, the difference is subtle. In comparison, I recently replaced the PHSE3 phono with the PH 5. WOW. And I more recently replaced the CD 3 MKII (upgraded) with the CD 7. WOW, WOW. Point being that if you go for the Ref II MK I, while it is not as coherent or musical as the Ref 3, (now considered by many to be amongst the 3 or 4 best line stages regardless of price) you will not be disappointed. Go for it.
Please forgive me for hi-jacking this thread. Since this thread seems have attracted a lot of Audio Research enthusiasts, I thought I might inquire about another, albeit more modest Audio Research offering; the LS 8 Mk II. Any thoughts or opinions on this less ambitious model?