I too have a nostalgic love for the original plastic Silca Impero. In fact I've collected about ten of them over the years. But they do have their weaknesses. Two of mine have gotten brittle and the barrel has cracked. I assume this is from too many hours in the bright sun. The other weakness is the plastic threads at the top of the barrel. An excessively vigorous pull on the upstroke can pop the plastic plug out of the plastic barrel and strip the barrel threads in the process. You can cut off the top section of the barrel and tap new threads, but you must also carefully shorten the plunger... and now your "frame-fit" pump doesn't fit your frame any more.

I have the new Silca "Tattico" mini pump on the bike I ride the most. So far (two years and 4 flats) it has worked flawlessly.

Brent