Not sure if they've been patched since but when it launched it was bad, the graphic enhancement was a lazy job of sort of upscaling that both made it loose the poligonal style (that in my opinion gives the games their characteristic look) and smear off some of the scenery texture to the point that some of the text on in game outdoors and store fronts gets blurred to the point of being illegible, and to finish it off it has a smaller music selection on the radios because of licensing issues

They've apparently fixed a lot of the bugs but people are still reporting that San Andreas particularly is still pretty broken. I personally prefer the original graphics so the definitive edition never really appealed to me but that's more of a subjective thing.