I have the AAZ Metal HG on my 1.6MF. Decided to do the mod after the leak on my stock HG became bad enough, just before last winter. I definitely recommend it, with some considerations I wasn't able to incorporate due to my isolated spot (i.e. no OEM VW parts nearby):
1) Take the time to measure the deck clearance, and get the notch size you ACTUALLY need. Lots of mechanics will use a 3 notch by default. I used a 3 notch to replace the OEM 3 notch, and I noticed a little drop in compression, namely tougher cold starts.
2) If you can afford them, go with some head studs. Stretch bolts are a bit goofy :? , and certainly are not as tough and accurate and reusable as studs. I believe raceware LLP makes them for the MF. Might as well if you're doin the metal HG anyways, and plan to run more boost.
Also, I didn't make any extra holes for the water jacket. Didn't need to.
Good luck!