I have a web site that should answer some of your questions at
[Link: stormloader.com]In short, Dave is correct, you can do almost everything with the 15-1994 that you can do on the Cinema 7, the main difference is that it is only a 6 device remote (but the home automation makes 7) and the volume punch through only works on the original VCR and CBL keys, it won't work on an AUX button re-mapped as a VCR button. (also, if you have the Kenwood VR-309 receiver, the 0313 and 0314 codes are missing). It's on sale right now for $29.99
The 15-1993 is a scaled down version. It's not designed to work all functions, just the basic volume, channels, etc. It doesn't have menu arrow keys for example, and the AUX button will work CD players, but not receivers. Having said that, it is a learning remote. It's not on sale right now, so you're gonna pay $29.95 for it also, if you wait for it to go on sale it will be only $19.99. If you don't need learning, you could get the 15-1992 which is identical except for the lack of learning and is on sale for only $14.99
Hope that all helps,
Rob