I own an MR78 and loving it. It has been one through with the caps being replaced. No problems recommending that tuner. The MR71 and MR67 are also quite good, albeit somewhat differently flavored (typical tubes v solid state stuff). Between the MR67 and MR71 I would pick the MR71. And if I were an equipment whore (please, no one be offended, I'm making fun of my past self) I would own my MR78 and an MR71! My days of owning multiple components in the same category are over. Well, almost- I do have 2 sets of headphones.
