From my understanding is that packet writing is pretty much a windows only thing... Each program that does it, does it as a propriatory model, which is mostly incompatable with every other computer or program in existance. Sticking to standards means increased reliablity and provides a level of safety for your data.
Imagine in 3 years if you burnt a CD using Nero's software and time comes around when you want to show off some old digital photograph, now what if nero isn't around anymore, or simply dropped support for the now-obsolete method it used? Maybe you can dig up a old app from 3-5 years ago and hope that it works with new hardware and new OSes, but that's only if your lucky. Were as if you used a normal format then it would be no problem.
But do what you want. I believe that apple naturally is able to burn CD-RW's with no problem, and then reburn them to add more info and stuff. I've done it a couple times, but it's been a long time. I don't use cd-rws that much anymore anyways, you can go down to newegg.com and pick up a 100 pack of ritek cd-r discs for 25 bucks(free shipping). And at a quarter a CD I think that's a pretty good deal. And CD-rs last longer, are more reliable, and are more likely to work in more cdrom drives.
Roxio Toast is the premier apple burning software. It's overkill for what I use cdroms for, but most people swear buy it and it's usefull if your into lots and lots of media stuff, even professionally. It can probably do the packet writer thing.
Here it is in a ad at apple's website