In reply to Stuart the postie: ME Drilight's the better fabric against moisture. Can't remember the numbers but it's got a better hydrostatic head meaning it'll cope better with rain/sleat/wet snow.
I guess you're comparing the ME Lightline and Rab Neutrino Endurance jackets? I own both and they're very different beasts, though pretty similar on paper.
The ME jacket is better suited to wandering round town, chucking in and out of vans, wearing on campsites, and generally taking a bit of a beating. It's a very hard-wearing jacket with tough outer fabric and has big pockets inside and out. One of the inside pockets will take a 1 litre nalgene - the rab jacket isn't really designed to do this. However, the jacket is a fair bit heavier than the Rab and the cuffs aren't great (limited adjustability) and the hood is extremely irritating if you're using it for climbing. I used to belay in mine in Scotland but it's a nightmare - the popper-off hood (ie. for around town) comes undone when you've a helmet on and the adjustability is negligible. The 'face flaps' are also a bit useless. However, for round town use and without a helmet, the hood is very good and very warm.
The Rab jacket probably won't take the beating the ME jacket will - the face fabric is noticably thinner. However, I prefer the cut of it (bit longer, less boxy) and it's a lot lighter. It's also marginally warmer, and the hood is way way way better, being genuinely adjustable and very useable on the hill. Cuffs are also better. I don't like the external pockets that much (they open too wide, allowing stuff to fall out easily if you don't zip them up) though, and the single internal pocket won't take a water bottle.
So, I reckon the Rab is a lot better for hill use because of the hood and low weight, the ME jacket better for day to day stuff because of its greater durability.