Are you able to have a decent place for $1100/month in rent + utilities? That just sounds awfully low to me even with a roommate. I could see swinging that if you didn't spend much time in your apartment, but it sounds like you do a lot of work there. I'm impressed, nonetheless.

I do think your comparison would have been a little better, though, if you had assumed the second programmer was single as well. Also, a salaried engineer at, say, Google, is going to get a lot more than $90k/year.