In its standard enclosure, the S1 was about the size of a refrigerator, just a bit narrower. A good friend of mine was a custom software consultant focusing on the S1 for large and/or governmental clients. She had a good tale about getting an emergency call from a large community college campus. All of their buildings had lost HVAC. They traced cables to a forgotten basement and found a long-unattended S1 that had been doing environmental control across the campus. It was completely clogged with dust.
Mine ran about 20 years at the wholesaler. IIRC, there were no serious hardware issues until near the end when the floppy drive started to fail.