Handcent SMS is by far the best SMS application I have used on my Droid Eris. The customization and ease of use lets anyone just pick it up and start typing. Oh! and if you don't want to type, no problem. It has a Voice to Text feature too!! It does take some time getting used to it and you have to speak clear and slow but it works! The pop feature is one of my favorites. You can choose to do a quick reply, insert auto text or use the Voice to Text. So I you're looking for a replacement SMS application and you want to have Threaded messages, Voice to Text, POP UP messages with quick reply then Handcent SMS is for you!!