I have something similar on a 10/22 and a SKS. It doesn't really seem to affect accuracy or functionality (the stocks just happen to be a good fit for me). The SKS usually is behind the seat of my tractor when I'm at the farm (coyotes) and remains indestructable.

Some are better than others. One I had, did not have a good locking system and the gun "bent" and wobbled at the hinge. Just not a good implementation of the design.

It also prevented me from getting a good "cheek weld" because of its shape. I could not repeat my sight picture easily.

My shotgun folder was excellent quality (and expensive) but the cheek weld was a big problem.

I removed mine from both my rifle and shotgun and went back to standard stocks.

The only SKS I have ever handled with a folding stock installed seemed to be more muzzle heavy that before. As for folders in general, other than the AR-180 I wish I still had, I have never seen one I really liked. I guess they are a love 'em or leave 'em kind of thing...

I like muzzle heavy. Faster follow ups usually.

How about getting a Kel-Tec SU-16C?

Try it, you'll like it!
I've had folders on Daewoos and Galils and they work great. For what you're looking for - a more totable, lighter (but not by much), storable package, it will work fine. A friend has one on his SKS and both of us really like it.