New tube preamp

Hi,

I'm thinking of replacing my PS Audio BHK Signature preamp and was wondering if anyone has listened to the Supratek Cabernet 6SN7 and or the Linear Tube Audio Microzotl preamps or the LTA MZ3, from what I've read the preamp in both of the LTA's are identical. Both are very reasonably priced (under $5000.00) and both are tube designs. For the money they are both supposed to be giant killers. Thank you.

Scot