It was good talking to you on the phone and thanks for the advise. Despite the warning that the Razorback upper might be finicky, I haven't found that so far. I have only fired 200-ish rounds of CCI Mini-mag ammo, but have not had too much issue. The cloth belt is tight, and I think that it caused some FTF issues, but other than three FTF (feed and fire) right at the beginning, and a couple of Fail to Fires (maybe the ammo?), it is running like a sewing machine! I didn't change out the hammer spring, but if I run into issues, I'll be sure to change it out to see if it helps.
It is a ##### to load the belts, but it keeps you from burning through all your ammo in 5 minutes.

You also have to make sure the belt feeds horizontally into the feed tray. If you let the belt hang, you will have malfunctions.
Wanted one of these ever since I saw them about 10 years ago, and I have to say, I'm glad I bought it! Happy happy joy joy!