Thought I'd drop that in just to help get things started.
I put one on the 'busa a few years back and I was happy with the increased visibility. Where before, it seemed like folks are pulling out in front of me, I would see a second look and stop.
My reasoning behind getting one was visibility. Standing out from traffic since it's harder to discern a motorcycle's speed due to the narrower profile.
Back in the 70's when I first started, having headlights on all the time on a motorcycle was made mandatory to improve visibility. With that, accidents dropped. And someone with their lights on would likely get a flash from oncoming traffic to let them know it was on since it would drain the battery. But with the auto-off of headlights now, car headlights are on more often than not. And many folks are turning them on anyway even if they don't have running lights since the car will likely ding at them if left on and the key is off. My 2002 Ranger does that. So we've been gradually losing our visibility. Gear does help with that in some cases but not everyone wears hi-viz gear
So I thought it was a step up in regaining visibility. I did seem to get more attention (more than being a hooligan anyway

).
A couple of years back, the unit fried on me and I sent it back to the manufacturer who sent me a new one for free. I connected it back up and it worked again but less than a year later I was having headlight problems. Finally I determined I had a short in the headlight harness, especially with the corrosion on the connector. I snagged a replacement from ebay and it's all good again.
Except that I didn't reconnect the modulator. It's still in the front end but I haven't reattached the wiring.
In part it was because I'd moved so I was less than 5 miles from work but also because trips were less and less frequent (most of you are probably aware why

).
I'm getting ready to take a couple of longer, multi-day trips this year plus more riding around now that I'm free to do so and in looking over the bike (cleaning, checking fluids, replacing the cracked water reservoir), I'm considering connecting it back up.
I do have the taillight modulator and haven't had a lick of trouble with it. Heck, other than the headlight one frying, I haven't had any trouble with the front one. I think it was mainly due to my riding in all sorts of weather that caused the problem with the headlight itself. With Rita gone, I have less of a reason to ride in the rain for 10 minutes and park it vs just hopping into the truck.
So, knowing this can be a hot subject, I thought I'd check on the collective wisdom of the group. I do feel visibility is important but I've also had almost no close calls in the past 3 years, likely due to being so close to work but also because I'm a pretty cautious rider in general. I did almost get run down by an idiot in a minivan when I was on my bicycle but that's a different thread
Carl