I have had minimal problems with most goggle systems and my glasses. I tend towards smaller frames though, usually pretty minimal titanium or half-rimmed or both. If you rock massive frames made of plastic and cover your entire FOV, it'll be a harder sell I imagine.
Tho I wonder, thinking now, if having glasses, the rims and arms really do kinda limit ones peripheral vision. So it seems that getting contacts or lasik would be pretty awesome for someone who plays a lot.
That said, yeah... E-Flex/E-Vents are pretty awesome. I plan to keep the ones I've got as long as I can.