I like using excel, it's pretty quick once you get the hang of it, not as quick as a calculator, but I still prefer it.

I threw your numbers into excel and got almost the same numbers as bearkat,

I ended up with you would have $374,417.1 if you didn't add any in, and if you added in just $1130 per month you could get to $622,010.70 in 13 years. This is assuming 0.4167% gains every month for 13 years.

If you have excel and want some pointers, let me know.