what vest? I don't see a vest.
If you're in the UK, Halfords have tabards on sale for a single pound in yellow or pink. And yellow waistcoats (not "vests") for £4.99. Go through the menus : motoring, breakdown, hiviz and use "private" browsing or you'll be getting Halfords adverts for years.
You can often get similar products from "workwear" shops for not much money because road workers get through hundreds of them.
You can often pick them up for free at the side of the road for the same reason. I've got through quite a few of these over the years. Quality varies a lot with the cheap ones, but the best one I've ever had was pulled out of a ditch.
I don't know if it's ignorance of the law or merely resentment, but in my neck of the woods I don't know that I've seen a single rider (besides myself) with the state-required amount of reflective tape on his or her helmet.
Oddly, I even see people wearing these safety vests, but without the tape on their helmets.
My gear - a bit less retro-reflective tape, but also fewer layers to deal with. First Gear Mesh Tech high viz, Bell Evo high viz, and (unknown brand) yellow goves. Plus, of course, a nice big Rat Fink patch from http://www.ratfink.com/.
If someone doesn't see a full-grown adult on a motorcycle with functioning lights, they're texting or looking for a french fry they just dropped between the seats. It's not because you aren't dressed like a safety cone.
The Hurt report states otherwise. I will err on the side of looking like a safety cone.
Wisconsin apparently requires scuba divers to use a dive-marker (essentially a float with a flag) when diving in their lakes. Coming from Illinois, I didn't know this until I actually got to the lake, and there weren't any dive shops in the area from which I could rent one. Off to the hardware store. We found that an orange safety vest with white duct tape makes a very convincing dive flag.
That is an awesome price for a high-vis vest. But I'd recommend headlight modulators to every rider in the USA as having a higher effectiveness, anecdotally, than reflective gear during the day. I'll agree reflective stuff rocks at night. 3M makes a fine retroreflective adhesive tape and there is a very cool neoprene collar called the Helmet Halo (need to replace every year or two because it stretches and loosens).
Headlight modulators that meet certain technical requirements (light sensing switch to turn off at night, specific minimum, not zero, certain pulse frequency) are legal by Federal law in all 50 states. I know this is not always true in other countries. I do notice drivers turning left in front of me much less often. I know it catches their attention. When I'm stopped behind a car even my reflection is annoying to me. Perfect!
You can get a similar one at IKEA for around $3.00. The only difference is that it fastens by velcro. It's perfect for my bicycle commute. As for motorcycle driving, I can see velcro being a inferior substitute to a zipper.
Perhaps, but as efforts to improve rider safety go, I'll take day-glo and retroreflectors over that "loud pipes save lives" bullshit any day. Loud pipes make you an asshole, full stop.
I did precisely the same thing as Jason: scoffed at the prices in the motorcycle stores and Amazon'd me a crossing guard vest. One benefit is that you can fold it up and tuck it away in the jacket so you have it when you need it.
They have to be kidding, wanting $80+ for these vests. It is really sad.
I will err on the side of looking like a safety cone.
Yes, but what about fashion?
If drivers are oblivious to large ambulances with plenty of hi-viz and lights and sirens operating (and very many drivers are), then wearing a fluoro vest when I'm on my bike is unlikely to keep me alive.
What WILL keep me alive is constant vigilance and the knowledge that I am indeed invisible to most drivers. I ride accordingly.
I agree - looking like a "special needs" person with one of these vests doesn't actually make any difference. Be defensive, that's how you save your OWN life.
Via Wikipedia: http://en.wikipedia.org/wiki/High-visibility_clothing
The Hurt Report found that very few motorcyclists involved in collisions wore high-visibility clothing, and that just over half of the collisions studied, nearly two-thirds of those involving another vehicle, were due to the motorist unintentionally violating the motorcyclist's right of way. "This dominant culpability of the driver of the other vehicle... emphasizes the special need for high contrast conspicuity for the motorcycle and rider." 
A New Zealand case-control study found that, if their odds ratios were unconfounded, the population attributable risks were 33% for wearing no reflective or fluorescent clothing; one third of motorbike accidents might have been prevented by wearing high-visibility clothing.
I was almost killed by a taxi driver, a long while ago, while riding a old Kawasaki GPZ 400 and some time before that got a brand-new ItalJet scooter all twisted by another blind driver (landed with both feet on his hood, where the bike used to be).
The longer you spend on two wheels, the bigger the chances are of some idiot taking you out (which is pretty much inevitable). The only way to solve this issue would be to increase the traffic penalties and fines - when committed against riders. No other solution.
P.S. [rant] When you see me on the bike, in traffic, just TRY for 2 seconds - not to muscle your car around and you won't ever see me again: I'll be gone. Takes a little bit of a brain, to realize this I know; but, no harm in me trying to explain it..:)