Hey ReddMcKnight,

That's a very typical question, as such I am going to reply with the massive help of a user on tombraiderforums named Zebra (you can go back to the source if you like, by checking out the AoD sub-forum) which breaks down the issues nicely and will give you all the info you need to know; what follows is a direct quote of the aforementioned user from that Tomb Raider site:

"There actually aren't a whole lot of bugs in the versions of the game you can currently buy as Core did a pretty good job of patching them out post-release (and all the versions available in digital stores like GOG and Steam have the patches included). The game's main issues are:

-The controls can be a bit clunky at times. (Which, I believe sasho's patch aims to fix. He's done an amazing job with that, though I would note that, from what I remember, not all of his changes are necessarily in line with how Core may have implemented things. Still, it's an awesome patch and has helped many people so if you don't like the game's vanilla controls, you should check it out. I'm just a nitpicking little purist so that's why it bothers me a little.) Also: Be warned that the controls get a whole lot clunkier in Kurtis' levels. Lara's controls in AoD never really bothered me but I found playing through his levels to be an absolute chore due to the way he controlled.

-Graphical glitches. Most of these aren't all that bad but you might occasionally notice stuff like missing or stretched textures here and there. (Nakamichi's level patch fixes a lot of that stuff.)

-Some story inconsistencies. There are a few relatively minor plot holes/inconsistencies due to stuff being cut out/moved around during the game's development. It's still a great story but there may be two or three moments that will be a tad confusing because there's a scene or piece of dialogue missing that would've explained it. No fix for that, unfortunately.

-Butchered strength upgrade system. This was originally supposed to be integrated into the story and make a bit more logical sense but they cut out the scenes that were going to introduce/explain it and had to change the way it works so the version of the system that's left in the game ends up feeling kind of arbitrary and at times confusing or frustrating. (Also no fix for that, as far as I'm aware.)

But yeah, some of the things AoD does incredibly well are: storytelling, music, atmosphere, animations, art direction, world building/characters,... It's a flawed game due to its troubled development history but if you can manage to look past those flaws you may just come to love it."

Basically: vanilla AoD is fine (bug-wise), but if you want to enhance the experience, use sasho's controls patch and Nakamichi's levels patch.

Finally, if you want to get spoiled, use the AoDSCU: the Startup Configuration Utility. Another user on tombraiderforums, HarleyCroft, helped me on this one by saying that:
"Not only can you select levels with it, use it to aquire double pistols, swim in the air anywhere you want to to fully explore the environments.. but what I personally thought was the best feature was if you die you can just press the fly button and revive! It eliminates the tedious need to reload after a stupid, unfair death"
I would use the AoDSCU only after the first playthrough.

Hope this helps!