For the most part a scope on an AK is generally only useful if your eyes can't handle iron sights. You are not going to get any sincere accuracy with any AK, I don't care what anyone says. The only truly good thing about the AK is for the ranges it was designed to operate in they deliver a terrific knockdown, that would be out to around 150 yards. The terminal ballistics are similar to a 30-30.
At one time I've had just about every variant of AK and only have one left. If you want the most out of an AK you should look for a milled receiver and chrome lined barrel. Another problem to overcome is the usual miserable trigger, that can be worked out or replaced. The best scope mount for the money is the Ultimak, it takes the place of the gas tube and allows for central mount of a scout scope or Eotech.
The scope mounts that fixed to the side of the receiver work OK, I prefer a cleaner more lineal approach like the Ultimak. There is also a method of mounting a scope with an adapted receiver cover, those are junk and will not keep a zero. The Ultimak retains its zero just like any well mounted mil-spec mount.
There were some people that reported that the heat from the gas tube and barrel would mess with the optics mounted directly above them, that may be true if sustained full auto fire were being employed. In my "real world" situation, I tried to get both an Eotech and Acog to become a problem by firing a series of magazines with a total of 120 rounds within a couple of minutes, neither scope had a problem. The Acog also works fine with the Ultimak but is a little more scope than is really necessary on an AK platform, it is designed for bullet compensation for 5.56 and is wasted money on an AK, put it on an AR, like my wife's.
The new Russian rifles that are allowed into country work just fine, I think you can get them in .308 which would be much nicer than 7.62 x 39, at least from an accuracy potential factor. Most of the people still using the AK platform militarily went to the smaller caliber models.
Arsenal makes a top of the line AK, they are not kits but factory manufactured and very nice weapons. If you are looking for a kit again look for a milled receiver, Bulgarian AKs were some of the best, Yugo rifles were also very well made and had stocks that fit better. If you know what your doing you can turn a Romanian G-code or Home Guard rifle into a good weapon, they were made from rather crude castings. I was never crazy about anything Century turned out, although the early stuff was fairly reliable.
If you can try to find the picture on U-tube that shows an AK firing full auto. There used to be a shot of a sheet metal receiver firing and it was like watching Jello wiggle, that thing is going off and wiggling and wobbling in every angle. Then watch the milled receiver model fire, not very much wiggling going on.
There were a few imports from Norinco back in the 80's that came out after the ban, they had full length stocks with thumbholes in the buttstock, really ugly. Some of them came with milled receivers and chrome lined barrels, they were called "Match Rifle" and had Chinese symbols stamped on them which when translated said "Very Accurate Rifle". I have one of those and it is the most accurate AK I ever fired. I modified it with a Dragonov type stock with adjustable cheek rest and rubber butt pad, the Ultimak scope mount and Eotech, I can hit anything I can see out to 150 yards, it has surprised quite a few people, especially AR guys that don't think an AK can shoot. Norinco also made a few rifles they called "Legends", they were also built on a milled receiver and had decent wood furniture and bayonet lugs, they were always top of the line when it came to what you had to pay for one.
I still think the AK is fun to shoot, ammo used to be dirt cheap and we thought nothing of shooting up a thousand rounds on a Saturday. I know a guy that legally shot a deer with an AK, which again is another advantage over the standard 5.56 AR. All you need in this state is a maximum 5 round magazine. Some of the Russian ammo is hollow-point which makes it legal, hardball ammo is not legal.
My son and his buddies loved shooting all my ammo up, when I put a stop to the free ammo Saturdays and told them they could shoot all they wanted as long as they provided the ammo they quit shooting, sound familiar?