I started rather late - in 2003, with the Escort ZR3.
This unit was purchased in conjunction with a Rev5 x50, which I transferred from my last two DSMs over to my current daily driver, my BL-chassis Subaru Legacy 2.5GT, and has since been updated to pair with the 9500i.
In mid 2006, I noticed that one of the front Shifter heads was no longer working properly, due to moisture ingress (after 3+ years and hundreds of thousands of road-miles, this is not unexpected). I undertook repairs myself which, once finished, I then realized that the in-cabin Integration module was also faulty. I then purchased a replacement module, and to this day, I still have the ZR3 on-car.
It was during this period, when I was trying to repair the ZR3, that I became truly active in this hobby community. Prior to that, I'd been, strictly, a lurker. At that time, in deciding on a replacement/upgrade for my ZR3, I purchased a set of LPPs, and it currently is also resident on my vehicle, with two heads facing front, a single head centered over the rear plate (the ZR3 rear head is placed at the bottom of the rear plate). Of the three heads that I have, two have, over time, failed (one within the one-year warranty period, the other shortly thereafter). I am currently waiting for LPP to come to a revision, for the TruSpeed, before also getting the defective head repaired/exchanged.
In the third quarter of 2007, I further updated/upgraded my countermeasures compliment, and purchased a dual-head Laser Interceptor setup. While I was a part of the initial-US-release batch, my 8.0 heads did not see moisture-ingress concerns until just this past winter (thus having endured a total of two, harsh, NE-Ohio winters), and even then, it was only one of the two heads. Laser Interceptor North America quickly replaced both of these 8.0 heads with 8.0A revision heads, under warranty. In the interim, I had also purchased two Slim heads to complete my rear protection, as well as purchased the Cheetah GPS-Mirror.
I recently purchased another dual-LI setup for my wife's new vehicle, and have moved my trusty old x50 there, too. In addition to the hardwiring for these devices, I also hardwired the lead for the Cheetah mirror into my wife's car, so that, when we do go on trips, I can just easily take the mirror off my car, and transfer it to my wife's.