It seems with five domains you would need a lot more than 6 MySQL databases, if you tend to use more than one database on each of your sites. You should find a host with more databases, you'll need plenty of disk space (if you run out, extra disk space is more expensive and in a lesser quantity) and you'll probably need more than 30 GB of bandwidth. $20.00 a month is way too expensive for what they are offering.
I have been using this hosting company and they are awesome, and even allow 5 domain names on one hosting account, unlimited MySQL databases, unlimited subdomains, three parked domains, 3000 MB disk space, 150 GB of bandwidth, control panel.... lots of features for only $7.95 a month. They also have 24/7 fast and live support.
Go here to see: http://www.lypha.com/hosting_plans.shtml
Hope this helps, seems this will give you what you need for less than half the cost per month than the hosting company you were looking at. :))