Meh, I wouldn't waste 99 dollars or get a 2nd one. I would just get a PS3 and call it a day. I am sure you have nothing but xbox games though.
I have both systems and loved my 360 for the most part till I got a PS3. I seldom play the 360 much anymore. Is already sold to a friend of mine when I decide to get rid of it, but keeping it till more games come available on the PS3 for now.
I had to send my xbox back once as well for something. I can't even remember, but wouldn't turn on. They took like a month to fix it and send it back.
Also my PS3 is much quieter than the 360.
Both good systems, just like the PS3 better, plus blu-ray FTW!