well since my last one got locked Ill word it in a different way.
My father in law is looking at a Mak90 sporter for sale, neither of us know much about ak's, is there certain things to look for as far as a manufacturer that is better than another, or different options or any potential negative things to look out for. Thanks for your help

Several things to look for!

First, you have to check the rear of the receiver to ensure it is straight cut, and not a slanted receiver. Straight cut allows standard type-56 furniture to fit, the slanted receivers have a funny angle and require special furniture. If the original thumbhole stock is present you may need to remove it to check.

There are also some, rare-ish underfolder receiver MAK90's and if you live free from an assault weapons ban, reinstalling an underfolder isn't that hard.

Next check that the fsb is straight and true by looking down the sights. If the frontsight post looks crooked, or is severely drifted left or right for windage, it is probably crooked.

Check that all of the major parts match.. Receiver/action, bolt carrier, bolt, gas tube, action spring guide/top cover retainer are all numbered, top cover may or may not have numbers.. mine does and matches.
Edited for spelling and a couple sentences..

thank you! probably a stupid question but is mak90 just the norinco version of the ak47? or does mak90 mean something else? and the sporter designation is just to satisfy the awb correct?

The AWB on imports banned some guns by name in 1989.  So they changed the name on the sporter type guns.  MAK90 supposedly mean Modified AK 1990.

Modified AK 1990.  Modified to be legal after the 1989 ban on evil features.  

Edit:  Beat me by 48 seconds.

awesome, thanks again for the help

Norinco MAK90's are nice AKs.  Stamped receiver is 1.5mm thick instead of standard 1mm.  Barrels are a little heavier too.  Like someone posted above, a square back receiver is preferred.  If the FSB is canted left or right it can be straightened pretty easily so it's not a deal breaker but it needs a little work.

It's not likely to have a canted sight or gas block, being a factory-made rifle. Most likely the front sight post will be near the center of the base and will have a corresponding index mark on the base indicating it was marked after test firing/sighting. Only minor adjustments would be expected on a factory rifle in good condition.

I STRONGLY disagree with the quoted post below.

I picked over three different MAK-90's before buying the one I have now. All three had some degree of fsb cant.

The MAK-90 & NHM-91 were produced as quickly as possible to make their way into the US before the assault weapons ban was passed. They all seem to show this and it's obvious that corners were cut.

For some reason, the older generation of small arms enthusiast regard the chinese AK's with high esteem, mostly in part to the Polytech Legends, which had great fit & finish. The majority of the chinese rifles had very nice triggers from the factory, too.

I don't mind that mine is a little crooked, as it shoots wonderfully, has the Norinco stamp on the receiver, and it was a rifle I was able to actually take home with me before the NY SAFE act passed, so I am kind of stuck with it anyway. I would have rather picked just about ANY wasr/soviet block AKM just for ease of modification.

you can always straighten a canted fsb.