I have tried most of the keyboards out there. I keep coming back to Touchpal because of how responsive it is when I press a key. All the other keyboards I found to be a little slow.
One thing to note is that Touchpal is coming out with a new version v3 in a week or so that might give you access to a full qwerty as well as the standard keypad they have now. Check it out.
http://www.cootek.com/forum/forum_posts.asp?TID=366