Same here. I still use my HP-41cx every day, with modules introduced in recent years by Diego and Angel. It was sad when HP discontinued the 41. The whole reason I got into the 41 was HP-IL, and then they want me to get interested in the 42 and other ones without HP-IL?? But although my 41 was so well made 36 years ago, I know there's the possibility that it go down; and although I don't use it to interface to instrumentation on the workbench much anymore, I have many other programs written for it that I use frequently, and of course there's also the familiarity and the invested knowledge I want to take advantage of; so for these, it makes sense to keep my eye on SwissMicros' development. It's great to have SM partially filling that hole. (I say "partially" because of the lack of HP-IL or similar which can be used to interface to lots of instruments at once. Maybe someday that will be there.)
How I got into the 41, and used it at work, and what I have in it now plus external accessories, and what I use it for now, is at http://wilsonminesco.com/HP41intro.html .