Gotcha.
My only experience is with the Title II side-folding stock but on the micro which I believe to be well-built, but honestly deep down I think that I would have preferred something more authentic like a parkerized, welded on stock of all steel construction. My version (I believe that this only applies to the Micro) was affixed with fasteners. The only issue that I personally had was that the two machine screws were a bit too long, extending into the receiver and interfering with the buffer however, that was easily sorted. Overall, mine isn't particularly comfortable to shoot but no wire side-folding stock is going to resolve that issue.
With respect to the Practical Solutions folder... I've only seen pictures on their website, but its aesthetics appear to be a little bit truer as it pertains to the spirit of the original style (but the Title II full-size stock is still good looking too).
It appears like both full-size stocks bolt on just like the factory under-folder. If that's right, then no modifications are needed which is great.
Final thoughts: Your selection really boils down to personal preference and despite how much feedback you receive on this particular topic I'm willing to bet that opinions will vary greatly.