positives and negatives on both, the question i would ask is what do you want more; text messaging or a better phone? The SK LX is a great device and it has a great value for the data plan! the Sidekick data comes with email, text and data unlimited. The Curve is a better phone when it comes to size and functionality with email and whatnot. The Sidekick is limited in the customization as with adding ringtone (you must buy them) as with the Curve you can poop anything and slap it in the ringtone side.