Rob,
I have two identical UEIC remotes of the RS 15-1924 (X10 UR24A) variety. It has basically the same capabilities as the 15-1994. It is 7(8)-in-1 with an older list of preprogrammed devices; and built-in RF support for P&P/X10 control which I do use somewhat. I'm not sure how much memory it has, but I have been able to squeeze 15-20 programmed buttons into it on occasion (and a maximum of 3 new 'protocols').
The main problem is the 'older list of devices' I mentioned. My equipment has outpaced the remote-it isn't preprogammed for my Technics SAAX910 Receiver and Panasonic A110 DVD. In the past, as I added those devices, I have successfully restricted what programmed buttons I put on the remote to a bare minimum to get by with my A/V setup.
But with the recent addition of a ReplayTV box, I can no longer live within the limitations of the remote. So I am in search of a replacement.
I've been lurking on a number of these forums, and trying to decide if it is worth getting a 15-1994. I've read through your web site, hack info, et al. And I finally went and bought one to play with last night. I figure I have 30 days to determine if it will fulfill my needs. And when I got home I determined that it is preprogrammed for both my VCRs, DVD, Stereo, and TV--which is a good start. Although the key mappings on the stereo S#CK!
So my question(s):
1) When you 'add' the ReplayTV to the remote, reading between the lines, I'm guessing you're adding it within the 'upgrade codes' memory of the EEPROM?
2) Is there still 1K of memory available for learned functions after your 'upgrade'?

I realize the following questions are probably best directed at the X10 forum, but with your experience, thought I'd give them a shot here--feel free to ignore them if there outside your experience:

3) Does the 15-1994 have RF support for X10. I can't find anything about it in the RS documentation or online anywhere.
4) If it doesn't, since it is so similar to the 15-1995, which has an internal RF transmitter, is it possible to add the RF feature to the 1994? Ie. if you've had the case open, is there an obvious empty spot(s) for the RF circuitry?
5) Any idea if that would enable direct X10 control with the proper home controller code (ala the 15-1924)? Or would I still need the RF->IR base station from the 15-1995 model?

Regardless of the X10 capabilities, I'm probably going to start using this as my main A/V remote and will be getting the parts necessary to build the hack circuitry. If you're not putting the software online for download, please add me to the list for the software.

Thanks for all the info, Q&A, and support,
David