I have both and I find that the fret like keys of the Bold do tend to mess up. This is due to of course how I type. Others might not have any problem at all. As for the missing key presses I did find that happened a lot until I upgraded the OS to the most recent and it seems to have gone away. It is totally user based and everyone will give you a different answer. I personally love the curve keyboard for functionality but the bold for its appeal.
I'm a little partial to my 8820, so I like the Bold keys better although I tend to notice more mistakes on the Bold and 8820 keys than the Curve's keys. Meh. I still type somewhat fast so itz all good.