I guess one of the most important things is what is the warranty like? Same as a new camera I should imagine.
Refurbished electronics are always a great deal -- particularly computers and camcorders.
Although, as Paul says, it's wise to have a decent warranty too (at least 90 days parts and labor). If something fails in a refurb, it's likely to do so within the first month or so, so make sure you're covered.
A few years ago I purchased a refurb Canon Optura 50 ( a predecessor camera to the one you're looking at). It worked fine (and still works today) and I never needed to draw upon the warranty it came witrh (aftermarket). I think a warrantly is important given the moving parts in camercorders.
good luck (the HV 30 is nice ... I recent purchased one)
To date, I have never had any problems with factory refurbs. Don't buy that many, as I'm usually purchasing when items are a bit too new for the refurb bin, but still, no issues.
I have a refurb Canon, though it did not start out that way. After about 4 years, the sensors died. Canon was doing a re-call, so they covered the replacement, though out of warranty. It's worked fine for the last 3 years. While not purchased as a refurb, it became one, and all has gone very well.