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
I like my REF 2 mk1. Uses tubes in the input and output stage. (Not a hybrid like the mk2). Sounds great with my Maggies.
The LS-5 is very nice if all of your other equipment has balanced inputs and outputs. I myself like the LS-25 Mk II.
Another vote for the LS-5 mkII. I have owned several of the others on your list and prefer this model over the rest for a quality tube sound. Adding premium Amperex tubes will greatly enhance the sound as well. Don DCCA Audio