although i must add its bad practice to have all your name servers hosted on 1 box.
imho, get a cheapy $15/year vps to run as a dedicated nameserver.
Yeah I know, IDK why they give you two IPS for nameservers and locate them with no redundancy. I don't really want to do another vps to run a nameserver, I was going to look into offsite dns hosting for the secondary. If i remember correctly there were some places that did it for free or very cheap.
However after a quick search it looks like it is not as cheap as I remember. Where can you get a $15/year vps?
It depends what it's for and is it mission critical. I didn't see a problem with this on my non-critical KnownHost VPS with a 99.9% uptime guarantee. And no big deal even if the data center were down for a short period of time due to upgrade or DDOS. I won't lose thousands of dollars in revenue.
Hosting is like a box of chocolates, you never know what you're gonna get.
BuyVM is a great place, they're $15/y and I haven't had any major issues for the time I've been hosting with them (since June 2010). At some point in the future they should be offering a cPanel dnsonly template. The $15/y will need it's memory temporarily increased to handle the install (throw in a ticket), but it should run fine on it afterwards from what I hear.