MS lost my business due to their atrocious failure rates with the 360 systems; won't buy another MS system
Unless you are in dire need of cash, I wouldn't drop either one. Both offer things the other doesn't and what's the harm in having choices? Even if you play one the vast majority of the time and you only fire the other one up a few times a year, you've already made the investment so why not keep both and enjoy what both bring to the table?