They are basically a modified Ak-47 with the long piston stroke attached to the bolt carrier, as opposed to the short piston stroke seperate from the bolt carrier of a true Dragunov or a Chinese NDM-86. This makes them a little less accurate. If you are firing the dirt cheap surplus 7.62x54r ammo through it, it not like you are going to really tell the difference.
The PSL has a stamped receiver, instead of the milled of the original SVD which is another minus point in my book. Makes it much cheaper and faster to produce though, and the mechanism is easily understandable.
Of course they are also far far cheaper. You can still find them in the $750 range, as opposed to the few thousand of a true SVD, so they are really good value for money, considering the quality, accuracy and general niceness of the rifle.
Some are also been imported that fire 7.62mm NATO rounds, though I never seen one of these in person.
I do wish they would allow the import of the Russian rifles into the country.