A while back, I was obsessed with getting my flash off camera, I used a coiled TTL cord, and that was fine... when I only owned one TTL flash. As I started acquiring more flashes, the use of optical slaves started to get less than reliable, also, the mix of TTL and non-TTL flashes made it so I needed a way that worked across the border, so I went ahead and bought the cheapest radio triggers I could find.
This were the CowboyStudio NPT-04, 4 channels, manual triggers. They weren't bad, and I have to say that for the price, they did better than I expected them to do. Now, they were ok for my collection of non TTL flashes, but once I started acquiring more TTL flashes, I also added a Canon ST-E2, which worked perfectly under controlled conditions, but it was an optical trigger (so, line of sight was important), and it could only controlled flashes on channel 1 and 2 (no third channel).
We started looking for options, we needed triggers that could work with our speedlites, but that could also trigger out studio heads, and if possible, they could control TTL on our Canon flashes... So flexibility was the key. I really wanted the PocketWizards (the plus III is one sexy trigger), but I would need to invest on one system and go all manual (plus some hotshoes with sync ports for some of my flashes without PC sync capabilities), or go with the Flex TT5 system and continue to use the old triggers for my studio heads, that, and the price, was less than desirable. Then I started checking the RadioPoppers (as I could integrate the ST-E2 trigger into the mix), but I ran into pretty much the same issues.
I almost gave up, then I saw a review by Lighting Rumours for the YN-622 triggers (and after contacting them and asking them some questions about it), I decided to give them go. Now, I'll admit that I haven't put these triggers to the test yet, for that I will have to wait until the 12th, but so far, I'm very happy with the results, and I am pretty confident that the triggers will perform as advertised.
I'll admit that the thing I like the most right now is that it takes the same batteries as my speedlites (so I'll only carry one type of batteries now... yay for little victories).