oh, my old friend! I still have my 11C, bought in approx 1985 timeframe. I toted and punched on that thing through all of college and many years on the job. Retired it a while back because the LCD is leaking black around the edges(?) I still have it though, and it works. A few years back when my FIL passed, my SIL was cleaning out and was going to toss his 15C.... I yelled "NO!!! that thing is valuable in some circles"....so I've got that one too. It's in much better condition than my 11C.