upgrade or replace rega planar 3

Inna, my Rega P-3 fit your description, it was flat, until I replaced the tonearm wire, the motor, the sub platter, the acrylic platter, and installed the heavy weight arm balance; after that, it sang.

Orpheus10, that would be almost a new turntable, and it probably cost you another $1k or so. I would just see no reason to do that, nor would I trust a company that makes "junk" in stock form, be it turtable, car or whatever.
By the way, I keep looking for something to post in that video/music thread. Nothing so far.

Orpheus,
I dont know whos review or what model of Sota Sapphire or upgrade Rega you are referring to, but I have owned a Sota Sapphire III and Rega P3, both using RB300 arms and the Rega isnt in the same league, not by a long shot, whether you are comparing bass, quietness, speed regulation, isolation from external vibrations, PRAT or any other item. Its just a better made and performing turntable. Have you actually owned and compared both?

Inna, you're right, it was about 1K. We set the bar so high that it's very hard to reach.

Manitunc, the Sota Sapphire is a fantastic table with a good suspension. The person who made the comparison was someone who had tweeked the Rega with the same tweeks I made. That should be here on the "Gon". When the tonearm wire is replaced with "Incognito" and the sub platter which uses a "Sapphire bearing", plus acrylic platter, plus "Techno heavy weight" arm balance, plus the P-3-24 motor; which is much quieter than the stock P-3 motor, you have an entirely different P-3.

I only record, and I use my Rega on the concrete basement floor. This negates the need for a suspension.

I agree with your statement in regard to the stock P-3 and the Sota Sapphire.