I did just that. I had both the 930 and 830 for about two weeks, together, side by side.
I have most the common problems on the 930, purple screen bleed, ran hot when using any CPU intensive apps, horrid battery and also its very heavy and slippery.
I could not tell much of a difference in speed between the 830 and 930, spec differences be damned. People spewing about specs are usually just specs peepers. Real world use is what matters to most people.
Anyway I sent the 930 back after two weeks and kept the 830 and have had no problems with it.
It's lighter and much thinner and not slippery, good battery life, doesn't get hot, removable battery and SD card support are huge to me.
Fred