Information & Advice specific to turntables

[MO Mark]

Hello all. This is my first post, so if I do this wrong, just let me know, nicely (I hope).

I'm looking for some information and some advice. I have 3 turntables:

Pioneer PL-516, with a Shure M75-6Scartridge, and a stylus with no markings, just white

Dual 1219, with an AT440ML/OCC cartridge, and an ATN103 stylus

Dual 506, with an Ortofon cartridge, and a white stylus with an 'E' on the front

What are your opinions on these turntables, turntable/cartridge combinations? Any suggestions on cartridge replacements? Also, any suggestions on stylus replacements for these cartridges? I'm not sure of the hours on these styluses, but I'm going to replace them as a precaution. I also have a brand new Ortofon Omega. Any suggestions on which turntable to put it on?

The following pics are of the cartridge from the Dual506.

Thanks, Mark.

p.s. I have either added two sets of pictures or no sets of pictures, 50/50 chance of doing this correctly. Even if it's not true, I keep telling myself that I am smarter than an inanimate object.