Well Tempered Classic or Technics SP10Mk2

bob - A couple of other comments - my WT was stethoscope quiet but theSP-10 had a much blacker background. The other change that I welcomed was the sense of precision and refinement that the Technics provided over the well-designed but decidedly Rube Goldberg inspired WT. The EPA-100 is a genuine contender for best arm ever made.
At it's age, the Technics you are considering will certainly benefit from R&R but they seem to work forever in the home environment since they were designed for round the clock abuse for 10 years in radio stations. I would look at the R&R as an upgrade path. Talk about the plinth is overstated. Yes, it is possible to improve upon the obsidian base but it is by no means necessary. All of this comes down to your mental state. How much do you want to obsess vs. how much are you willing to spend?
After all, have you changed your monofilament regularly? How about the silicone bath? All tables have moving parts and they all wear. They all need maintenance and they all benefit from rehab. Pick your poison. I, having experienced both would prefer the SP-10.

The factory-supplied electrolytic caps in an SP10 are now upwards of 30 years old. The lifespan of an electrolytic cap is less than 30 years. After 10-20 years, they start to leak DC and can even leak electrolyte onto other circuit elements. It is quite normal to replace an electrolytic of this age, empirically. Other than that the SP10 is pretty darn bullet-proof. Modern electrolytics are superior in performance and longevity to any that were available back in the day of the SP10, so your new caps will last even longer now than originally, until the next such service becomes necessary.

Macrojack alluded to it. And IMO, the weak point of the WT is the tonearm, as he inferred. The table itself is a very clever design. I have much (frustrating) experience fiddling with the WT Reference tonearm on the WTR that belongs to a close friend.

Macrojack,
What is R&R? Bob

I think it means rest and relaxation literally. My use just means rehab or repair or refurb or renew or restore or ........?

Bob, looks like you have sufficient response to make your decision. But I'll add a little reinforcement.

Years ago I owned an original (square motor) WTTT and arm. It played music but was responsive to improvements such as the new black platter, a clamp on the fluid cup, and damping on the arm tower. Still, as Lew suggests, the WT arm was always in question. For one example I could never get the same tracking force measurement two attempts in a row. What kind of precision does that suggest?

I replaced mine with a Kuzma Stabi/Stogi Reference table and arm. This was a significant upgrade offering extended bass, increased overall dynamics, and much better decay, most noticeable on piano. More recently I've listened to an SP-10 Mk2 and even with a (temporary) compromised plinth, it shows potential for bettering the Kuzma.

The step from a WTTT to a Technics should be a no-brainer.