i own currently, 4 studio lites...3 of them have the m3 electronics, but are rewired for my preferences. one is standard.
i did at one time own 5.
duncan screamin demon/hot stack neck/dimarzio evo neck, the evo is kinda hot for this guitar...and can be muddy, so if you use it, back it off a good bit...it really cleans up nice though if you ride the knob.
screamin demon/duckbucker bridge/ a2p neck - easy to use all these together..they all sound great.
duncan custom/hot stack strat neck/a2p neck -same as above..really easy to like them all...very clear in this guitar...the custom really defines and brings out the top end these guitars are known for..
and the other has matched zebra duncans wired standard les paul wiring: duncan custom/59' neck. the 59 is a great all around neck pickup. it's clear, big and defined.
they all sound phenomenal to my ears
the one i traded also had duncan custom bridge/hot stack strat/a2p neck and i think the pickups are what sold the guy on the trade.
the alnico 2 pro in the neck is a huge win in these guitars too..they match really well with the brightness and you can get some great violin/organ type tones with the right tube distortion.
i know a lot of guys dont like SD and dimarzio pickups around here, but, you asked about studio lites, and well, since i own a couple with differnt PUPS, i thought i'd chime in.
pickups i have tried in them too..and hated. duncan distortion (way too muddy) , dimarzio super D (nice and thick, yet, really bright..didn't like it with this guitar), invader (YUK!), pearly gates (wasn't too bad, just too weak honestly for my taste), alnico bridge (again, more of the same..not hot enough in the bridge), evo bridge (undefined and muddy, kills the tone of this guitar similiar to the DUncan distortion, but evo's breathe a little more in these guitars), tone zone (not much tone coming out of it...but a lot of top end/hi mid bite...which i thought was strange cause it sounds great in my Epi paul in the neck), paf pro (it's ok, but the 59 is better and the customs or demons win out for me every time).
all in all, you cant go wrong, obviously, imho with a demon or a custom in the bridge, and the a2pro neck.....those 3 just really match up with the guitar and also balance well between them for different tones, but not out of place with each other.
good luck.
also, i will tell you, i matched my first lite's pickups from SD up by using the tone chart...fuck, like 15 years ago in the catalog! found what i thought looked like it would sound good, and went and bought them..put them in, and lo and behold, were exactly what i wanted them to sound like.
dont let people fool you with the "chromyte"/balsa wood downtalk either..these guitars a pleasure to play, own and experiment with tones...they have a great personality and again, when matched up with the right pickups, and a set of graph tech saddles, they can sing, roar and shine with the best of them.