Having had both - a Lance 915 and an Outfitter Apex 8 - I would agree that the one huge difference is that you cannot just stop & go stealth. You need to raise and lower the roof every time even if you just want to fix a sandwich. And the popup was quite noisy compared to the hardwall.
Also the popup did not fare as well in cold and rainy weather. It was dry allright, but still you have the wet fabric, and that is all that separates you from the sometimes not so great outdoors.
When it is warm and dry and nice and sunny, nothing beats the popup :-)
