I'd like to try to balance all of the negative comments about the 9500i by giving my opinion that the 9500i is a great radar detector. I've had a V1, an RX65 and an X50. Out of these, the 9500i is my favorite.
It seems that based on a couple of potential issues with the 9500i, many people here have concluded that the 9500i doesn't work as advertised or that it's not a good detector. I disagree.
The first complaint seems to be that the detector will not pickup a real LEO at a location that has previously been locked out. Even if this is true (which I'm not convinced it is true), this detector is so quiet without even using the lockout feature (because of the speed-sensitive sensitivity) that this is an insignificant issue to me. The detector is worth the money even if you decide not to use truelock at all. More importantly, the odds of ever getting a ticket by driving through a previously locked area and then not picking up the LEO are extraordinarily small. Your odds of getting a ticket from instant-on or laser are so much greater that this becomes another non-issue (trust me, your detector is worthless against instant-on or laser despite what some people say about signals/reflections from the car ahead). In short, a detector merely reduces the odds that you'll get a ticket, and the fact that the 9500i may (or may not) have certain unlikely situations in which it is not flawless is insignificant.
The second complaint is the ramp-up. I, like everyone else, wish this worked better. However, this brings me back again to the point that this detector is so quiet. Unlike other detectors, you need to slow down when the 9500i beeps at you... it's probably a LEO! Thus, it really doesn't matter that there is not much of a ramp-up.
Until you've tried a truly silent detector like the 9500i, you can't imagine what a difference it makes. I don't think any other detector is of any value in the city due to the false alarms. This is especially true of the V1, which became worthless to me because I quckly got so that I tuned it out mentally. In fact, I've driven right by speed traps without ever noticing that the V1 was alerting me. The X50 and RX65 were much better, but still unusable in the city. I would much rather have the perceived imperfections of the 9500i than this problem. At least I use my detector now, rather than keeping it in the glove box because it's too noisy and annoying.
Obviously there is some give and take when it comes to a particular detector's approach to false alarms. The 9500i is at one end of the spectrum (silent), which may mean that in some limited circumstances it might filter a true LEO. The V1 is at the other end, in that it doesn't filter anything. I'll take the the silence, but some others may prefer to be alerted everytime they drive by a store.
One final note. Even assuming that truelock doesn't work flawlessly, that doesn't mean that the 9500i doesn't work well or as advertised. Navigation systems don't always get you from point A to point B perfectly, but few people think of their system as a piece of junk because of it. Rather, it's accepted as a limitation of the technology.
In short, I think way too much weight is being given to the perceived problems with the 9500i. In my opinion, the benefits far outweigh any problems.