L600 sounds great for lead guitar, heavy rhythm. I'd say I like the L600 better for a smooth sound without being muddy, clean is good for Jazz at low impedance. I like the L500's better for blues, crunchy sound, clean (with Q-filter). The L500 is killer too in heavy music, the bass is very punchy when you increase the pup height close to the strings. I got 1 L600 about 7.9 henry (custom), one 4.8 (that I love, thanks Becky!!!!). My L500 is an XL. With the experience I got, I see no reason for having high inductance pups (including the neck pup, i.e. an L500C would match an XL perfectly) . My L600 4.8 henry is replacing an L600XL (I already got my 7.9 henry so...) and I still use a Q-filter. Lowering the impedance of the pups and using a clean boost in front of the amp dramatically improve the definition of my dirty sound (I actually do the same with my L280's in my clean channel). I use to increase the impedance (with the Q-filter) when I decrease my guitar's volume on the dirty channel for keeping the hugeness of the sound... I've now reached the "tone heaven". There's no doubt, Bill Lawrence is a Genius! The major characteristic of the L500 I think is the clarity of each notes in chords even with a ton of gain. The L600 is more beefier in the dirty channel. For easy pinching harmonics the lead version is plenty enough in both models (IMHO), if you like the sound of the midrange then go with the XL (with Q-filter is better). Hope it inspiring you folks.