Moon neo 310lp combined AT art 9

No experience with your gear, except the ART 9. Fantastic value cart(for the 1k price point) with my tubed phono amp.

The Simaudio gears appears to be quality SS gear. Likely, the onboard phono stage delivers a good amount of their stand lone unit. Advantage being one less box and cables.

With that in mind, the value you put on the possibly minor/subtle improvement becomes the issue. Note I prefaced minor/subtle  with possibly. Someone may chime in with experience with similar gear and actual results.

I found going from a SS phono to tubed the game changer. If you read reviews of high dollar SS units, its often mentioned how it sounds tubed. You put up with a little noise for "real" over a decent SS unit. In my case, I need to crank the volume up to 12:00 o'clock to hear hiss, and I just don't do that

I have the Simaudio MOON LP5.3 RS Phono Stage and it is superb. The 310 looks identical (internally) from the photos I’ve looked at

The card in the 350p shares the power supply - the 310 has it’s own excellent power on-board supply and the circuitry of the 310 will be superior.

You have more flexibility WRT the cartridges you can use - the 310 is very configurable for both MC or MM

It responds very well to good power cables - i don’t feel I need to get the separate power supply that is available with the 5.3.

My 5.3 is extremely quiet - only a slight hiss (no hum) at full volume

It will be in my system for a very long while

I’m a happy camper :-)

Regards - Steve

P.S I just noticed there is also the 320S power supply for the 310,

But as stated above - with a good power cord the 310 performs extremely well and there is no second box to take up additional room

Regards...