I have an SKS, I'm building an AR. The main difference to me is I get spoiled to the trigger and usability of the AR. But at the same time, I bought the SKS to have a rifle I'm not afraid to take out and beat up, and not be anal about keeping it clean.
If I wanted to do some improvements on the SKS, like a better trigger, a stock, and techsights, (all of which I might still do eventually,) and keep it compliant, I'll wind up spending three times more on the rifle than I paid for it in the first place.