definitely then check the timing. when the head was off the crank might have turned slightly. the shop might have checked cam timing but if the crank was off then everything could be F'd.

 

By all means take it back to the shop. Give them an opportunity to complete the job they started. I know it is frustrating, but a good tech should be as anxious to see the car as you are to get it sorted out. Give them a chance to get it right. Could easily be something like a rotor and cap problem.
These cars take a lot to get sorted out. In your situation a good tech is a must-have, so talk to several shops, get second opinions and ask a lot of questions. The policy of a good shop is to educate their clients - you should come away from every visit with them with a fresh understanding.

 

Okay, it's back in the shop, and I'm awaiting word.

Guy said they should be able to sort it out, since they did a 928 just recently, but my confidence in them is somewhat shaken.

We'll see.