I'm thinking about picking up some night sights for my HK USP; but had a couple questions.  I would mainly want the night sights for IDPA use.

Do you think you have faster sight acquisition in the day with night sights, or just at night; compared to a standard three dot?  What kind of a lifespan do most sights have before they lose their glow.  

Trijicon and mepro are the better of the n/s available. If your primarily going to be using your pistol for idpa, I would go with a Heinie target. It`s plain, no dots. but it`s faster to acquire the target as there are no dots to line up, just place front post in the rear. It doesnt sound faster but it is.

I have Mepro's on my 30. Installed when it was new.
They are warranted for 12 years.
I am well over 1500 rounds and 2 years and have noticed no change in brightness.
They were less than the Trijicons but Probably not as durable as their tubes are rubber mounted in the sight.
Rich is correct about the Heinies.

Trits will draw your eye slightly better in the day than normal sights, and at dusk they are worth every penny.

I'm looking at trits for my USP too. I like Ashley Express sights (sooooo fast), but they don't make them for USP. Ghost Ring works just about as well, so I'm wavering, wait or buy?. (the USP, and the group buy AR made me broke, why I'm worrying about this now, I don't know. Could it be...fun? [:D])

Anyhoo, I think Trijicons do seem to be brighter than Meprolights, but the Mepro's are a bit cheaper. Entreprise Arms has the ghost ring Trit set (front and rear lamps) for USP at $139.85 I like Novak, too, but they don't make a USP set. Trijican fixed sight set is 115.00, Meprolights at $100 bucks, Mepro's seem to stick out a bit far. MMC has 'em, but I don't know their product, so I can't comment.
I'll go with Trijicon.

"Where," you ask, "is he getting these prices?"

Brownells. either www.brownells.com, or call 'em and ask for a catalog, ph# at the website.

I have to throw my .02, again.
The Ashley Outdoors nite sight has a large visible dot, largest for pistols, I believe.
The downsize of these sights are they have a rounded top (front post). Any range work and especially idpa longer range stuff will leave you frustrated. It is hard to alaign the tops of the rear with a rounded front post. It is very fast for very close range work.
Ditto for their ar15 front n/s post.

Ummm... I jus actuall read your post thouroughly, HKer...

EYE-DEE-PEE-AYE

I sorta missed that part, mabe you could make it more obvious for a moron like me next time. [:)]

IDPA? I use Millet for target work (I have Millet's adjustable on my Taurus PT92, don't laugh, it's accurate!). Ghost rings are not any more suitable for long rang work than Ashely sights, though I would want either of them on either of my defensive pistols, not target sights. I think defensive pistol means just that, defensive, and I want the fastest sights possible when I'm defending my self. Tritiums probably won't pay for the cost distace, if this is a noontime only pistol for IDPA.