Only good ones are iPhone and HTC Sense. I have Swype and it's great but really takes some getting used to as it's totally different than the rest of them but it becomes insanely fast.
The HTC IME keyboard is available for any Android phone, except AT&T's. Essentially, the same as Sense. Its decent, and better than the stock Android keyboard, IMO. The XDA dev who was maintaining it has set it on hiatus though. The Droid X's MultiTouch keyboard was nice too, but it doesn't work with Froyo yet and activating it also futzed with my settings for the hardware keyboard, so it became useless.
I'm pretty solidly in the hardware keyboard camp. With a hardware keyboard, you can type far faster and more accurately than any soft keyboard will allow, and without losing half your screen to the keyboard. For quick, short text messages to friends, the soft keyboard is fine. But for typing longer messages or more detailed emails, the hardware keyboard is a must.
I am glad to see more hardware keyboard options, the myTouch 3G Slide, the Epic 4G, the LG Ally, etc. Would like to see them offered on more carriers and price points though.