I had a ranch stainless during the 90's. It functioned well but wasn't real accurate, my $450 mini-14 shot about as consistent as a $90 SKS did. I was told by a few different people that the only thing that -really- fixed that was putting a match barrel on it. There's lots of little tricks and tweaks you can bother with, but really-->just putting a good-quality barrel on the gun ALONE will amount to more than all the tweaks will.
Other options are: Colts, for a tinkering/tackdriving semi rifle, this is what I'd go with. EAA has some AK-variant guns available, Saigas ($200, typical SKS fit and finish) and VEPR's (much nicer, $500). The EAA guns are available in a few different calibers.
The main advantage that the mini-14 used to have was that it was a semiauto that could shoot the huge amounts of cheap surplus 223 amo that was available back then, but the mini-14 cost $200+ less than a Colt rifle. Back then, there were no cheaper 233 semiauto rifles at all (in the US). Now that you can get much cheaper AK's in the same caliber, the Mini isn't real attractive for any reason.
The mini-30's didn't seem to have nearly the consistency problems the mini-14's did. I would not buy another mini-14 at anywhere near retail price unless I lived somewhere that did not allow other options. The -most- I would pay for a mini-14 now is $200, and that would be a new one.
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