I started with one and now I have four of them. The Vespa Grande is great, but a Solex in it's own weird way is cool.
So what if it will only do 20MPH on a good day? I raced a 12 year old kid on his BMX bike for laughs (his) and he really thought he was something. But the truth is that if we were racing for distance, he'd be dead tired after a half mile while I'd still be going without breaking out a sweat.
And if treated with some semblance of care, they can last damn near forever.