Well...I suppose unstable is the wrong word. Emerald just hasn't gotten as much attention from hackers as the other games. There are many utilities that have trouble hitting Emerald's offsets properly. The original version of my current hack, for example, had to be discarded due to sound corruption. (This was before the R&D post regarding Emerald's sound corruption, which thus far has made a huge difference.) Beeping sounds are a minor annoyance at best, but I'm a notorious perfectionist.
Short answer: IMO Emerald requires the hacker's full attention. It's a love-hate relationship.
EDIT: Accidentally posted on my own profile. Please ignore the man behind the curtain.