External enclosure for DVD burner: fan important? TDK OK? ..

I have an extra 5.25" Pioneer internal DVD burner I want to put to use
and am looking at external enclosures for it, preferably with Firewire
connections. My main question is, are fans necessary? I could
understand for an external harddrive, but some posts elsewhere imply
that heat can be a problem with burners too.

Does anyone have experience with the supercheap TDK enclosures, that
go for under $20? Obviously they're partly plastic (though not
entirely, as opposed to the Galaxy cases from what I've heard) but
they look pretty sturdy. Macally makes a gorgeous aluminum enclosure
for $45, and I understand metal cases dissipate heat better.

So, is a fan advisable? For infrequent DVD burning, is a cheap
enclosure OK or just wasted money? Should I stick to a Firewire
connection for greater speed?

Thanks.

I have used cheap firewire cases for many, many years on all of my
computers, buying bare internal IDE CD and, later, DVD drives. I have
never had any problem except early on with Double layer when I got a
lot of burned DVDs that did not play properly, usually screwing up at
the layer transfer point. But that was all with Memorex DL writable
discs, and once I switched brands I never had any trouble again.

One thing I should say about the cheap enclosures: I have used dozens
of them for hard drives also, and now and then a bridge board fails. So
while it's statistically very unlikely to have one fail, ever, under
light use, under continuous use I'd estimate a 10% chance of a board
failure every 2-3 years.