I shot an AR equiped with one this weekend, and it was great.  The guy was able to fire so quickly, that I thought at first that it was either firing bursts or full auto.  (the rifle was also HBAR with a Y-Comp brake---it really rapid fired beautifully and accuratley).

I am torn between buying this trigger and the JARD trigger.  Price is within 5 bucks of each other, with the JARD having a slightly lighter pull, although I worry that the JARD may require fitting).

I want a light pull with drop-in easiness (no fitting by a smith).  

 I want a single stage, light trigger, with drop-in easiness---any ideas on which one is best?

well then you do not want the JP...
if you buy it then you will be required to
adjust the take up and over travel as well as time the disconnector and grind off enough metal on the trigger to fit the selector.

but i enjoyed putting mine in and it it just like you said.  i think you will learn alot about the rifle and have a little fun installing it.  my trigger is plenty light for a semi-auto and i don't think i want to go much lighter.  

I had to do some light fitting on my JP.  It's been over a year since installation so I don't remember exactly what surface I had to modify, but it was well worth the effort.  The trigger has an excellent feel.  

I remember using some CLP on a piece of 400 grit sandpaper and then polishing with a stone.
The instructions were actually well written and quite detailed.

Some have said that JP's accompanying "Speed Hammer" is too light to fire hard-primered rounds.  I have not personally experienced this, even with a wide variety of ammo.

I just sent my lower off yesterday to Metalcraft Specialties to have the Fire Control kit(trigger, disconnector, & hammer) installed.  I chose to let he do the work as he charges $205 installed.  Brownells wanted $180($144 dealer) for the parts alone so I figure $205 installed is pretty good.  These prices are for large pin Colt, small pin is less.  He seems to have alot of experience with the JP, so a little extra cash is worth it for having it done right the first time.  I searched here alot before sending it off and several people said it took a fair amount of time to install.  One guy said he took the trigger and hammer in and out 30-40(probably exagerating) times to get everything right.  My time is worth money to me to.  I will not pay a mechanic $45 an hour to work on my truck because I can do the work myself and I will show a greater attention to detail.  I will pay a good gunsmith $45 an hour, because I do not want to take my life in my own hands hoping I got it right.  

I installed the JP single stage trigger a couple years ago.  I didn't have to do any fitting as I recall, though if I modified the disconnector I could probably lighten the pull a little bit more.

It will be installed on an otherwise stock Bushmaster Dissipator.  
 The trigger is terrible on this damn rifle, despite the slight improvements that I have made to it through some buffing.  The damn trigger still sucks!

I have decided against the JARD- I don't like the design, and the damn thing doesn't allow the NRA-mandated 4.5# pull for some of my matches.  I want something that a smith won't have to touch, that will give me a pull from about 3lbs to 4.5 lbs.  

 BTW, it must be single stage...
...looks like my options are pretty much limited to the JP adjustable trigger.
 

If trigger weight is an issue, check out the JARD website. (click on the "Order" box for trigger spring info).  www.jardinc.com
They now have trigger spring kits for up to a 5 lb. pull.   I've had two JARD triggers, one of the first ones out and one of the latest design.  The first one required some fitting and was a bit too light, (trigger had to shortened to clear the trigger guard and I cut a new trigger spring for a heavier pull).
 The newer model required no fitting at all. I got the 3 lb. trigger spring and it is SWEET.

Installation is pretty simple, but it helps to have a slave pin handy for installing the hammer.  I made one from an old drill bit.
The biggest problem that you can run in to is the sear engagement set screw.  It uses the same hole as the pistol grip screw and if it's not threaded all the way through, you'll have to thread it yourself. If you don't have a 1/4 inch 28 thread cutter, a trip to the hardware store will be required.  

If you do get a JARD, be sure to use Loctite (comes w/trigger).   I use it in a setup with a 14.5 heavy barrel w/KKF A3 brake and ACOG TA11.  It is very fast....unfortuneately, I'm not.