Played it for almost an thousand hours on the PS3. Yep, all modless hours. I just like the game that much. Problems unique to the PS3?
Well, when it crashes, and it will, you will have no choice but to hard-reset, but there are ways to circumventing it if you can spot the signs of it occurring. They are few and far between though.
Game breaking bugs can't be fixed by the UOP, and obviously, if you fall afoul of one, they are inherently very bad. You can either educate yourself of them (but risk minor spoilers), or make numerous different saves. There's not auto-save button on the PS3 (though there is autosave when you do things: fast travel etc...), so you'll find yourself pressing pause -> save -> etc... a lot. Honestly, it becomes second nature, it does take longer than hitting F5, but you will have more security for it, and like I said, you don't even realise you've saved you end up doing it do fast unthinkingly.
Otherwise it's fine, the rest is preference.
I have it for the PC now, and have all the major mods, game revamping ones like OOO. They're alright, but I'm not irritated I didn't have them in those 1000 ish hours. They change quite a bit, but it's nothing utterly revolutionary. The nicest fix is level-scaling, but a smart build can get around it anyway. I would recommend playing without them, highly, for your first run anyway (with the exception of UOP, and maybe a level-scaling fix).