A resizable window would make it considerably slower. I suggest you temporarily reduce your screen resolution to 800x600 while using it (ideally on a second monitor), then the window will nearly fill the screen if you really need to see the window larger. Alternatively, use Matrox DeskNav or similar desktop magnification utilities (windows built in magnifier is rather unweildy).
I imagine that part of the problem is a lot of you are running at 1280x1024 or higher, I find the modelviewer adequate at my standard resolution of 1024x768. For me the limiting factor is monitor refresh rate, I look for the maximum resolution that still supports 80hz or greater refresh, I'll subject my eyes to nothing less. If you are looking at 60Hz I feel for you - I can actually feel my eye refocus at that frequency, it is most uncomfortable and can't be good for you. Maybe I'm just getting old and need bifocals or something though!
What bugs me about the modelviewer is the error on exit in XP.
edit: I love the disclaimer in the text file:
Quote:
Because it is an internal tool, we do not guarantee its compatability with your computer system. It works fine everywhere we've used it. That's about all we know. We have no reason to believe that running this software will transmogrify your computer into a Vic20. If it does, however, it's not our fault (though it's sure interesting). Basically, use at your own risk.
Keep arms and legs inside of Model Viewer at all times.