(If that's all you want from them, aren't there cheaper solutions? These are "full VR in glasses form factor")

Not sure. I mainly still use a Quest 3 as a monitor replacement and had no strong reason to switch. The prescription inserts I got with these weren't quite right for my prescription and I prefer using my actual spectacles. So I've only used them to port stuff to/develop for - and tinker with existing apps (mainly the google supplied stuff as the embargo only lifted yesterday so there wasn't much released for it specifically).