Unloved? I have one purple one, two white ones, and a green one. They are spread out in years between late 60's to mid 70's. The earlier ones had no safety levers and a very small front chainring for the time, 36t. The newer ones moved up to 40t.

They are on Craigslist pretty frequently. Parts are not that hard to find. There are college kids converting them to fixed gear leaving derailleurs and other parts available.

The only changes I tend to make are to keep the original Rigida wheelset and cogset, but I have alloy wheelsets with different cogs that I use depending on the kind of riding I plan to do.