... to be honest the Crawlers were a little too dark for me anyway (I know others will say they don't find them dark, but they were in that particular guitar!! :P )
"We like the dark! Dark for dark business!" 8)
Anyway, since I usually chime in with support for Crawlers, I may as well do so again -- though it seems plenty have beaten me to the punch.
I have a Crawler set in my 1993 (I think) LP Std, installed after much "which BKPs?" agonizing that was settled by email from Tim explaining why I recommended the Crawlers. And I soon decided (a decision confirmed again and again since), that he was right.
I play a range of styles, from classic rock type things to doomy metal, and one of the great things about the Crawlers is their versatility. You've got the classic vibe there, but also plenty of power to crank things up, as well as a bit of push in the mids to help cut through. They also coil tap nicely, just to add to that tonal palette. Basically, you just point your amp where you want it, and you can play whatever you want. Plus, as someone pointed out, the neck pup is way tasty! :)
That said (and although we like the dark), the Crawlers are not the brightest pups in the world. 8) I think they sit beautifully in a LP-style guitar, but if you want something to brighten the tone up, then Tim's other suggestion of Rebel Yells is a good one.