This one from Advanced Armaments in Ar15 Accessories link at:

advanced-armament.com/

What do ya'll think?  Is it stable/solid?   Hard to install?

Information
AAC Accessory Mounting Rail
    Mini $42
    Mid-Length $49
   Full-Length $59
1" QD Ring $17
KAC Vertical Foregrip $59
M3 Illuminator $139
Surefire Universal Light $165
Package Deal-Accessory Rail & KAC Foregrip $99 *
Package Deal-Rail, Foregrip & M3 Illuminator $229 *
Package Deal-Rail, Foregrip & Surefire Universal $255 *
* Package Deal includes Mid-Length Rail"

BTW, what is the "M3 Illuminator?"

^BTT  

Anyone?

I'm trying to solicit opinions - ANY opinions - before I blow up to $300 bucks on this system...

I am not sure about a flashlight (that is the M3 illiminator, a small but powerful flashlight that can also be used on Glock handguns), but as far as the vertical foregrip, one can be found for $15 at: http://www.m-aparts.com/ar15m16.html

I just bought a mini maglight and mounted it under the barrel with a Tac-Star universal barrel mount and used a remote pressure switch that can be purchased at:

http://www.wholesalehunter.com/product/tacstarl/tacstarl.htm

Also, I recently purchased a UIFR rail made by GG&G from Lightfighter Tactical that seems to work very well. It mounts just like the Advanced Armament one, as far as I can tell, and took only about 5 minutes to install. Plus it was only about 46.00 with shipping.
http://www.lightfighter.com/item.jhtml?PRID=1144225

It seemed to fit nice and solid to the hangduard and was slighly cheaper than advanced armament. Or you can order it directly from GG&G at http://www.gggaz.com

THIS IS A BIG RIP OFF!!!

You can get a weaver rail for about $10.00.
nuts and bolts for 1.00 and some little washers made out of a piece of scrap plate metal and your set to build a light mount for the ar-15.  then get a surefire light and a 1" weaver rifle scope ring .and your all set for 75.00
you can mount the base on the bottom of the forearm using bolts that go thru the vent holes or roatated on the upper right side.
the most expensive part is the light and i caution you to go with a good light!  the recoil will rip a cheep light to pieces.

308wood, have you tried this?  It sounds like a great idea, but how do all these parts fit together?  Are you suggesting to drill through the rail, then use nuts and bolts to attach using the holes in the lower handguard?

Also, with a Weaver rail, would you still be able to use a KAC foregrip?

Take a look at these mounts:

www.zukem.com/sjm

Also, I bought my M3 from:

www.botachtactical.com/intecm3tacli.html

The price is now $125 (of course one should be aware that they have the worst customer service in the history of capitalism).

And finally, the best price I've seen is $50 for the KAC grip (and from what I hear, there's the KAC grip and the DSArms vertical grip - everything else is of marginal quality).  Check it out here:

www.rangerarms.com/knights_armament/accessories1.htm

YMMV, buon fortuno…

The M3 is the Glock-mounted tactical made by Insight and marketed by Streamlite.  These are very nice units.  They're a 6volt light that isn't quite as bright as the Surefire.  But you can get them for $115 (or less, if you're lucky) and they're a much better package than the bulky Surefire's.  I put on on my CAR with the Insight mount ($15) and it's positioned perfectly for the left thumb to toggle.  Insight also makes a switch with a pressure pad which replaces the standard switch ($45), which would go well with a K grip.  I got a good deal from Botach for the light and mount, but getting delivery was a pain.  They seem to be getting better.

Thx for the input guys.

Quoted: 308wood, have you tried this?

yes

It sounds like a great idea, but how do all these parts fit together?

from bottom up"
machine screw.
rail
hand guard hole
custom washer
nylon lock nut.
the washer is larger than the holes in the hand guard.   when you put it all together the nylon lock nut will protrude thru the hole in the heat shield.  just for fun you can drill some holes in the rail to allow for ventilation.  when you buy the rail get one that is flat  or slightly curved on the bottom (flat browning A-bolt?).  

Are you suggesting to drill through the rail, then use nuts and bolts to attach using the holes in the lower hand guard??

YES!!!

Also, with a Weaver rail, would you still be able to use a KAC fore grip?

Yes

this probably violates some copy rights.

Thanks for the clarification.