Philosopher - 10:02 pm on Nov 10, 2011 (gmt 0)
Normally, IP's aren't a big deal, but you mention you have some moderate interlinking. For this reason, I'd be inclined to insure that you continue having separate Class C's.
There are numerous "seo hosts" that offer this so it certainly shouldn't be an issue.
Why not just call your host and explain and see if they can continue offering you that. That will let you know what you need to do next...if anything.