That's the shop right off of route 1, basically across the highway from the Edison Diner right? I think it has rod iron gates around the lot. They are ok, and do competent work, albeit a bit pricey from what I have heard. They also sell a few MB's and BMW's as well as the occasional Porsche.
The German Car Shop, is on rt 27. Basically to get to them from Rt1 take the Highland Park / 514 exit from rt 1, basically in front of European Moterworks. Come down the ramp, you'll see a bunch of used car dealers. Make your first right. You'll be traveling through a neighborhood. GO 23 in the 25! Highland Park cops are ruthless. Absolutely ruthless. When you come to your first light (about a mile) make a right. Keep on this road, (should be 4 lanes, two in each direction of travel) Stay to the left. The road will narrow, The German Car Shop is 4 or 5 miles down on the left hand side, right before a railroad underpass I believe. I dont have a Plainfield / North Brunswick phone book handy, but I'm sure they are in there.
I would take it to them, get their opinion, and see which works out better for you, financially. Also if it is a head rebuild, you may be better served to buy a remanufatured head, and swap it yourself if you are mechanically inclined.
Let me know your experiences with each shop, and how it works out,
Best wishes and take care,