I'll bet that would match brass legs nicely.

For what it is worth, I recently upgraded the cabinet speaker in my JD. I've previously used Flipper Fidelity in a different machine - they are awesome, but I think I can get 75% of the upgrade at 25% of the cost.

My prescription for cheap bass:
1) A 6.5 car woofer. I have tried three different ones, and I found that this matches the DCS sound system (which is capable of some decent deep bass) nicely: http://www.amazon.com/Lanzar-VW64-Watts-6-5-Inch-Subwoofer/dp/B001JI6FFG/ref=sr_1_2
2) An L-pad wired into the backbox speakers allows you to attenuate the backbox speakers, thus increasing the relative volume of the cabinet (bass) speaker: http://www.amazon.com/L-Pad-50W-Mono-Rated-Shaft/dp/B0002KR1EQ/ref=sr_1_1

L1AT can not cause an opto problem, but L1AT does make the machine more sensitive to opto problems. Many people (including me) have opto problems that were never noticed or diagnosed until they installed L1AT. (You can reinstall L7 and probably confirm that the opto still doesn't work.)

L1AT also seems to be more sensitive in setting switch problems. For example, if you do not hit a switch after many games, the logic sets that switch as potentially faulty. Because I suck, I am always setting the fault for the third captive ball switch with L1AT, but L7 seems to let the switch go untripped for longer before setting the fault.

LED OCD doesn't handle the GI lighting (at least not yet). The only solution I am aware of is to use incandescent or disable dimming, as you already noted.

Wow. Was there anything in particular that you scored particularly well on? (Did you bang out a few hundred million on the ultimate challenge or anything like that?)

Has anyone else noticed this:

Any multi-ball before achieving the Ultimate Challenge results in a normal 4-ball mode with a brief ball saver. However, once Ultimate Challenge is completed, starting a multi-ball results in an endless ball saver mode.

I'm not sure if this is a bug with L1AT, but it certainly doesn't seem like an opto problem. (I have never had an endless ball saver with any multiball prior to completing the Ultimate Challenge, but any multiball after UC has always resulted in an endless ball saver.)

New flipper toppers from Laseriffic for Judge Dredd: http://pinside.com/pinball/forum/topic/metallica-flipper-mod-by-laseriffic/page/3#1466109

I used Cointaker non-ghosting LED's for the inserts and they worked fine.

The new Pinball Life LED's are also non-ghosting.

Q1 - be sure to check that your flipper end of travel switch works correctly. It's possible that it is not working and thus causing your coil to get overly hot, especially if you tend to hold the flipper up.

I installed the Deadworld mod and had great difficulty getting the crane to move consistently. Then I installed teflon tape (see link below) and the crane became 100% reliable. After I made this mod and dialed in the crane, it never missed a ball in approximately 4 months of play. Personally, I like the Deadworld mod because there is nothing else like it and I personally hate virtual locks.

http://pinside.com/pinball/forum/topic/judge-dredd-mod-to-make-crane-lift-much-smoother-and-consistent

The diverter should divert the third ball shot through the ramp.

The "Blackout" mode does use GI dimming effects. Therefore you have two choices:
1) Stick with incandescent bulbs
2) Use LED's, but turn off GI dimming in the menu.

You should check all your optos. My JD with Deadworld mod never behaved that way including the times a weak shot caused the ball to go to the Deadworld. It seems your machine doesn't think a ball is on the ring.