I just ran across these guys today, has anyone here heard of /see/used one of their 80% milled receivers? 

https://tortort.com/

Yes, he's very popular in the building community. Do a search over at the AK Files and you should get a lot of info.

Well I figure if I have to experience the pain of an unfulfilled build, I may as well share the misery 

I did one of Tortort's 80% Galil receivers and was extremely pleased.  I did it myself with simple techniques - drill press, angle grinder, dremel, and of couse files.

Using the supplied dimensions and measuring very carefully and using quality cobalt metric drill bits, I was able to drill all the required holes.
Using an angle grinder caregully with a thin cut off wheel I was able to cut the bridge and ejector area out and finish with dremel and file.

If you have scrap receiver sections from a demil these help for connecting the dots and removing some of the trickier cuts - like the trigger and selector area on the bottom - The selector slot on the bottom I used a dremel cut off wheel and old section of demil receiver screwed to it as a guide - came out great.
Barrel install was fairly easy - no issues with mine.  I had an existing used barrel, but timed to headspace without regard for exisitng block orientation and just re-drilled for the new orientation - Yes it means I have two gas port holes under the block - one new on where it timed and the old one  - which was covered.  no big deal to me as it works.

The only thing I would say is the finish is a little rough - You can sand it smooth.  I used KG Gunkote flat black and it came out great.