The original Mini folder was a rattle trap, would wobble when worn at the joints, and was a PITA to deploy or fold.
Most of those that think them "cool" have never used them extensively.
In addition, the wobbly Ruger folding stock was mated to a fairly fragile plastic pistol grip, and a wooden stock, which in addition to suffering all the common faults of wooden stocks, was often a very loose fit to the barreled action, thus effecting a double-negative whammy to accuracy.
The modern stainless steel Butler Creek side folder has none of those flaws. However, BC ought to emplace a sling stud at the toe of the butt for sling attachment.
Opinions above based on having used both. FWIW, simply swapping out the barreled action from the Ruger side folding stock into the BC side folder had a noticeable positive effect on accuracy.
YMMV.