I've tried nearly everything out there, with a few different mini's over the years. The problem with mag compatibility seems to be because of the build quality, and loose factory specifications of the mag-well area of the mini 14. Also, the front mag attachment point is different on the mini, especially the early 181+ series between the standard model, and the ranch model. That said, there were also issues of quality and specifications between the different aftermarket mag manufacturers.
Ramline - generally fit and worked well with all my minis, with the exception that bolt hold open after the last round usually didn't work.
Eagle - these plastic mags were visually thicker than most of the rest. Would fit and function in a standard model, but not a ranch model.
Federal Ordnance - These metal mags fit and functioned well in standard model mini's and about half of the Ranch models. These mags were a little thicker than factory mags, but not as thick as the Plastic Eagle mags. The metal quality of there mags were better than most others.
Precision Magazine Inc. ( PMI), and "American" brand magazine. When Federal Ordnance went out of business, these two companies were their successors, and the magazine quality stayed the same.
"Original Equipment", (OE) mags. - These are not factory Ruger mags, but are sold by CDNN. The build quality is very good, and they will fit and function well in most mini 14's. The problem with these magazines is that the green follower has a somewhat gritty texture, that will cause some failure to feed issues. Replace with a factory Ruger follower ( from Midway) and these magazines work 100%.
Pro-mag - current production promags seem to fit and function well with my mini's. Replacing the follower for a Ruger follower helps with reliability with these mags. The problem with promags is that their build quality has varied widely over the years. When the 1994 federal "assault weapon's", and magazine capacity bans were in the process of being passed, pro-mag was going into overdrive putting out crappy 30 round mags for the mini 14. They had straight bend lips on top, rather than the usual rounded feed lips. Avoid these rush job pro-mags like the plague.
Current production Pro-Mags are decent quality once the follower has been replaced. Avoid buying used pro-mags, or Gun Show Pro-mags.
National Magazine Co. - These metal mags are often sold by online sellers. These are about the same quality as the Rush Job pro mags. Save yourself time and heartache. Avoid at all costs. These are bottom of the barrel junk.