SOTA Cosmos and other models - lean sounding?

Montaldo, I have owned SOTA tables since 1981. I currently have a Cosmos with a 4 Point 9 on it.
To answer your questions,
#1 Absolutely not.
#2 No way to account. Too many variables. Bad system, bad ears, who knows. Put the two tables on the same system with identical arms and cartridges and 99.9% would never hear the difference. 
#3 None
Your Sapphire is pretty recent so you should be able to apply all the new upgrades including the DC motor and drive and the new magnetic bearing. Call SOTA with your serial number in hand and ask. If your current table is in good shape just let SOTA rebuild it to current spec. It is just like getting a new table.

Mike

1+ mulveling. People who use idler wheel turntables either don't like bass or don't have subwoofers. They all rumble like express trains. They are why rumble filters were invented in the first place!
montaldo, we all get that urge for a change. It is that urge that has led me down the path of destruction on several occasions. Stick with what works.
All good turntables, those that do not add to or transfer anything to the process of reading a groove sound the same. Those that sound different in any way are adding something that should not be there whether it sounds euphoric or not. 
As an aside. I have a 192/24 copy of Dylan's Desire and the MoFi 45 RPM version. We sinced them up and on first listening all three of us there at the time thought the vinyl sounded better. The vinyl had this glow for lack of a better term and it made Dylan sound as if he were standing out there at some distance. The digital version sounded as if Dylan was standing right in front of you singing into a microphone and on closer inspection the digital was more detailed, the violin in Hurricane had more rosin to it. So like Nelsen Pass's amplifiers the vinyl is adding something to the process we like. Nelson is right when he says audiophiles don't care about accuracy. They just want to be happy. I think I just contradicted myself.

Absolutely no argument montaldo. Nobody can know what accurate is because they were not there at the time of the recording as you suggest. It is chasing an illusion. "Sounds real" and "accurate" are in reality isolated from each other. There are annoyances that are common to all threads of audio enjoyment, noise of various types, IM distortion, cartridge miss tracking, wives screaming, etc, that are easier to discuss and manage in an on-line forum, the technical issues. We all see something different in an ink blot. Maybe sound is the same. I want an instrument to sound real but my real may be and probably is different than your real. 

Gee wspohn, what do you use in your first system:)