I had one for a few years. Even now as I fiddle with much more expensive table, i miss it. it had a much quieter noise floor than the Rega Planar 2 that replaced it (i was actually very surprised at how loud the Rega rumbled compared to the PL-550). The Pioneer also had unfailing pitch accuracy and speed stability. That heavy platter is truly a thing of beauty!
It is the manual version of the PL-570, but the 550 has a shorter tonearm than the 570. you'll want to mount a low-compliance cartridge on it. Look for relatively heavy recommended tracking forces, at or over 2 grams would be best. i ran an AT440MLa on mine and realized only after some time that it wasn't good match for that arm, the arm is too heavy and the 440MLa too compliant. This was made very obvious to me once i mounted the 440 on a Rega RB250 arm. It opened up and delivered a much more refined sound. This was not a fault of the Pioneer at all, simply what happens then you put a cartridge designed for a lighter arm on an arm that's too heavy for it.
I don't know what your budget will be for a cart, but I bet one of the Denons would be a perfect match.
Another plus of the 550 is the ability to adjust the vertical tracking angle. just loosen the two long, thin bolts on the tonearm mast and it can be moved up or down. One trick i figured out was to put a jackknife-type set of feeler guages between the gap in the post to set the VTA. To gauge it higher, I'd open more blades of the feeler gauge in the stack; to lower it, I'd take a few out.
(You probably have to be looking at the arm to make sense of this)
EDIT TO ADD:
Oh,wait! I found a picture of the arm.
Stick a feeler guage in the gap around the arm post---that is where it moves up and down. Leave the guage in there when you tighten the bots back in, then pull it out once its snug.