Love, love, love this jacket. I was pretty skeptical in ordering it since there were no reviews, but it seemed to be what I was looking for so I took a chance and it paid off. The jacket is really lightweight - so much so that I was worried it wouldn't keep me warm, but it does the trick. I wear this on early 5 am runs - with temps as low as 15 degrees, along with a mid-weight moisture wick top underneath and it's perfect. The pockets are zippered, which I need to keep a key in. The back is a tad longer than the front, hits my mid-bum which is good. I ordered a small which fits great over the single layer beneath. I'm 5'2, 115 lbs and the small is good, wouldn't want to go smaller. The trick to this jacket is that it blocks the wind but vents out the back so you don't get cold. There's also a tie at the bottom to tighten for really windy days (or if you wanted to use for biking). The velcro on the wrists make it easy to adjust with your gloves on. I've been using it for about a month but haven't ventured out in the rain, so can't comment on how it'd hold up (I can't imagine that it's water repellent).
As far as visibility - the yellow is that same bright lemon yellow of other jackets you see out there. There is reflective striping on the front along the zipper and the back along the vent flap. There's a few other spots with reflective spots, but I was expecting a little more. It seems like they should have included it on the cuffs since that's the part moving the most. I wear gloves that have reflective palms, so not a huge deal for me, but that's might be the only reason I'd consider 4 stars vs. 5. Also, I just noticed on one of the pictures, the cuffs are yellow...the one I have has black cuffs (with the nice velcro close I mentioned).
When I placed the order I received a standard email from Amazon stating the item would be shipped in something like 3 weeks. Then I got an email from the company in the UK saying to ignore the timing from Amazon and it'd be there sooner. I got it in about 7 business days, perfectly reasonable. Just a little "clunky" in the communication.
Price - can't beat it! All the local running shops around me have these types of jackets(Brooks, New Balance) for twice as much for the same functionality.
Hope this is helpful!