Don't go cheap is the main thing I can say. It will save you much frustration and the stuff will last a long time.
I absolutely, 100% agree. For me there are just two viable ways to put a red dot on an AK, and only one way to put a conventional scope; you can do an Ultimak rail for a red dot or scout scope, and a Krebs/Beryl/TWS style rail for a conventional scope or red dot. IMO, everything else is either junk or has some serious limitations. This assumes that the gun needs to be 100% reliable. If this is a fun plinking gun, your options expand somewhat.
I have an AK with a Irondot. The mount is OK, the sight itself is marginal. I was using it as a trunk gun and the last time I pulled it out to check on it, the battery was dead. It was less than a year old. Aimpoint batteries are good for, what, 5 years, with the scope turned on
. Since this is a "serious" gun, I will be replacing the Irondot with an Aimpoint Micro, and moving the Irondot to a plinker. Pity, since I liked the concept.
Sidemounts put the red dot up too high, and have some stability/return-to-zero issues. Plus, the whole assembly acts like a lever and allows you to really torque the sidewall of your sheetmetal receiver.
The TWS/Krebs/Beryl rail looks good, and is the only good way to put a conventional scope on the gun. Just be advised about what it can do to your remedial action drills if you have a malfunction. You have to decide if it is worth it or not.
For me, AK + Ultimak + Aimpoint Micro = Win. Everything else has too many shortcomings.