jones: I've got the Meg's portable too and it's not a replacement for the porter cable that's for sure. I use it when I go car shows or as a quick method of final buff. I've tried to put some NXT with the cordless and, while it does slow down the buffer considerably, it works fine.
The best results I've gotten with this product is using an mf bonnet for a final buff. I've also gotten good results with spraying qd on a finishing pad and going over the car right before a show.