Upgrade Opinions, Thorens vs VPI


I'm looking to possibly upgrade to a better turntable.

My current setup is a Thorens TD166 MKII with the original tp11 tonearm. The table has a few mods including a solid cherry plinth and birch bottom with sorbothane feet. It also came with the 10mm spindle bearing, same one used on the TD160.

Amp: Rogue audio Sphinx 
Preamp: MM preamp built into the Sphinx
Cartidge: Shure M97xe with SAS stylus
Speakers: Monitor Audio Silver 8

The components listed above are my recent upgrades. I now think my table is due for an upgrade. 

I am considering installing a Jelco SA750D tonearm on my Thorens, since the tonearm is likely the weakest performing part of the table, or going with a completely new table.

I am considering the following tables:

Rega Planar 3 (possibly not a big leap?)

Rega RP8

VPI Classic 1 

Acoustic Signature Wow XL with Rega arm.

I am leaning toward the VPI, partly because I really like its look, but I do want the best sounding table under $3000 (subjective I know). Overall, I'm pleased with the current sound from my Thorens, so maybe the best bang for my buck would be a new tonearm. Some members have claimed that a Debut Carbon will blow the doors of a TD166, but in my personal experience, it's the opposite. So I'm thinking I'd probably need to spend over 1K for a real sonic upgrade over my Thorens.

Anyone have experience with VPI tables versus Thorens TD16X series? Any advice is welcome.
helomech
Ray et al.... What I’m saying is that sure...a better turntable, better plinth, better this, that, its all better....but I predict, that putting the very best turntable in the system with these components would not be heard. The Thorens is a very good turntable....The VPI may be better, but the difference in sound on this system is neglegable.
No doubt.....just buying a Prime will beat a 160 series maxed out mod. However, I think the only thing he has left is to replace the tonearm on his, as other mods have been done. 

Might as well, I say. That is only 500 as opposed to 3000. Upgrade the cartridge...phono stage and enjoy. Then see if the table is really the next step....if so, save up for a Prime. 

Or, just buy a Prime now. You can't go wrong with that move

BTW, Matt and Harry just modded the 3d arm. Darn......don't they know how to stay out of the Garage? lol

Harry modded the arm, Michael Fremer introduced it right after his Prime review, then yesterday on Facebook, Mat said that there’s no way they are going to offer the mod, because drilling the 3D arm carries too much risk of damage......general consensus is the sound was about the same.....introduced mostly to negate the criticism of the unipivot being wobbly when cueing a record.....
My Thorens will be maxed out for the most part, after I replace the tonearm. The other mods I've done have improved the sound slightly, but I have a feeling that a new arm will yield the greatest improvement and elevate it to another level. I already have the armboard for the Jelco, so in all, it would set me back about $1100 to install the new arm and a better cartridge (considering a 10x5). 

Of course, that's about one third of what it would likely cost to get into a Prime. I highly doubt a Prime will sound 3x better than my fully modded Thorens, as my table already sounds very good to my ears. My gut feeling is that I'll be well into the territory of diminishing returns once my Thorens is maxed out. I'm also thinking I might get more bang for my buck if I replace the tonearm and spend 2k on a cartridge, rather than spend 3k on a VPI and 500 on a cartridge. 

I'm fairly mechanically inclined and I enjoy modifying and improving things. Part of me feels it would be a shame to relegate my Thorens to the closet after all I've invested. It went from a humble $200 Craigslist find to a beautiful (piece of art in my view) table that produces very satisfying sound in its current state. 

If a Jelco tonearm and better cartridge yields a 20% improvement in sound, I think I could live happily with my Thorens for a long time.
And I'd have a lot of dough left for black discs and maybe a new listening chair.