Just played the first mission and made sure to get a good look at the city to make sure everything was rendering.
I can safely say it's gone from the worst PC port of all time to a rather average one. I'm not sure if it's something I have enabled or a part of the game now, but it seems to be capped at 30FPS. On the other hand though, it holds that 30FPS very well, and while there are occasional drops for me, the stuttering and horrible performance seem to be gone.
The radio is still horrible quality, but it seems that there are mods to fix that (although with the changes made, mods might not work for now). Also, I didn't know this game had proper headlight shadows from cars. Very nice feature for something from 2008, and I can actually appreciate it now that it functions.