Lockbox Comparision

I just attended a board meeting last night regarding whether to switch lockbox systems. We currently use the Supra System which I really like because of the Technology. With a Blackberry add-on coming out and the new key this seems to be a great system. The reason for this discussion is that a larger board next door is switching to the Sentri-lock system. It seems form the presentation that this is an inferior system and that it will cost more business wise when they come out with technological advances because they have to be purchased separately. I was wondering if anyone uses this SentriLock System and if so your thoughts about the differences between the 2 thanks.