the dimarzio 36th anniversary is a great pickup, one of the few non-bkps that really impressed me, but it's far from the classic paf sound
it's considerably hotter and fatter than the original dimarzio paf from the 70's (which was actually a gibson t-top replica)
it's definitely hotter than a mule as well, bassy like the vhII and middy like the black dog, so it's hard to call it a real PAF
also, it's hard to beat BKP's clarity when you put some heavy gain
dimarzio, duncan and gibson pickups tend to distort and mud things up too easily
the riff raff sounds really thick in my les paul custom, but mine has a custom thicker magnet, so it's a little bassier than a common one
having it close to the strings really helps
my mule in a jap hurricane les paul copy doesn't sound that thick, but thick enough for me
it's the juiciest and most organic bridge pickup I ever played
when I need more push out of it, I just use some sort of booster (usually some maxon/tube screamer or my juansolo baby boobtube)
the vhII set also sounded great in that same guitar, but it's a punchier and more defined sound, clearer under gain, but not as sweet
I also have a black dog in greco lp std, which is quite bright and has a maple neck, and it makes it sound thicker and gainier than my lp custom, which is a naturally darker and bass heavy guitar
for early UFO, I'd probably pick the riff raff over the others, but all these options should work pretty well
I really like the subtle natural compression of the mule when you dig it hard
