I have a valentine and it works well (for what it does). $100 would be a good price. But......I rarely use mine anymore. The advent of new radar guns (if used properly) will still get you. That, combined with all the other things that operate on the same frequency as traffic radar, means lots of false alarms, making it essentially useless in urban settings. Also, the V1 needs an audio module if you are going to hook up the alarm to your helmet.
Also, the defacto speed limits, on open roads, have crept up to the point (in most cases) where you can comfortably ride 75-85mph with little risk. However, with cities/towns using traffic fines as a revenue source, strict adherence to their speed limits is a good idea.
If I was going to buy another detector, I would get a new Escort Max or 9500. At least it will "learn" where the false alarms are and not respond. Still does not protect you from a properly operated newer radar gun or from laser (yes it does detect laser but again, properly operated laser cannot be detected in time).
One other thing....you reduce your chances of getting just a warning, instead of a citation, if you have a radar detector IMO.
I am sure you will varying opinions on the V1 and detector use in general, but the above has been my experience over the 30 yrs of owning/using various detectors (20 yrs of V1).
Rod