remanufactured head or new engine for E36 M3?

Hello, I just signed up for the forum and this is my first post. I'm the original owner (drove it off the factory floor in Munich myself) of a 1995 M3. Recently bent values. My current mechanic speculates it's bent values b/c the #6 cylinder has lost compression. It died under moderate-to-heavy acceleration while at about 5K rpm. No big loud noise, just sudden loss of compression. The mechanic said I should swap the engine even if it only needs a new head. Does this sound right? Engine has about 180K on it. If I replace the head, how much in labor should I expect to pay? Also, are there any complications with replacing the head which would make the engine swap a better plan? Any recommendation for a mechanic who could give a second opinion? Here's the real complication: wife wants me to shoot the old horse and just let it go. I want to keep to it, but can't if it's a money pit. 

e36m3