[Spiderzilla] 503 error

[RCA]

I am having trouble downloading this site:
http://www.vgmusic.com
It works great for a while, but then it downloads files that say:

503 Service Unavailable
In order to keep our bandwidth usage in check, and to prevent people 
from carbon copying our site, we have instituted a limit on how much 
data can be downloaded at one time. If you are seeing this message, you 
have exceeded the limit we have set.  You will be able to resume 
downloading sometime in the next 15 minutes.

How do I get around this limit?
Thanks!