(I also treat disk burning ability the same way - slot load drives are limited use)
I've heard that, but it actually hasn't been my experience. The slot-loading drive in my MacBook has burned a startlingly large number of CDs.
When I first got the computer, it would burn CDs but not DVDs; it shipped from the factory with a defective drive. Apple replaced it for me under warranty. Since then, the drive has been awesome.
The company I'm a part owner of ships the user manual for our products on CD, and I usually burn the CDs myself. In addition, we produce multimedia sales CDs that are tuned to different distributors of our product, and ship stacks of those CDs to the distributors. In one two-month period, I burned, without exaggeration, more than 2,000 CDs without difficulty. This computer has almost certainly burned over 6,000 CDs in its lifetime, with no problem at all so far. (We can't economically mass-produce the CDs because the ones we ship to distributors contain different content, depending on the distributor and their target market.)
I've been bugging the money people to get a CD duplicator machine, but the CD burner in my laptop has been extemely reliable.
