TT, 12" Tonearm. Who tried and ended up preferring 12" arm?

I have to err on the side of Lewm regarding dustcovers.
I will be blunt and state I have no idea what causes the difference but playing with the dustcover in place and then with it off is akin to lifting a shroud on the music.
It sounds corny but it is more open and dynamic with dustcover off and this is from THREE separate tables.

I use the dustcovers for two reasons.
To keep dust off the tables when NOT in play.
To provide a nice resting place for my tired old cats who otherwise would sit on the darn platter I am sure! 

Everyone knows dustcovers down close in the sound. :-)  I found that out on my LP12 back in the 80s.

Metal lids do the same thing to tube preamps. 

Apparently not " everybody" it seems ....

Seller says he is shipping my TT monday from Canada. I re-arranged everything, made a big improvement in stability I was putting off, ordered a tempered glass shelf for the monster.

12-inch tonearm made of cocobolo must have very high effective mass. Fine for low compliance cartridges. Not so fine for high compliance ones. There is no single best length or best material for a tonearm.

@lewm

18g, since there is no detachable "headshell" on my version of Reed 3p we can only add the mass of the cartridge and screws.

So when you mount an MM on your Fidelity-Research FR-64s the "problem" is much more serious than with Reed Cocobolo. I think the mass of FR 64s is twice as much. However, you reported a good results with MM, i also can say that 18g Reed was superb with mid compliance MM cartridges (Garrott p77, Victor X-1 and X-1II, Glanz 61, AT-ML180 etc).

I bought my Reed especially for ZYX Premium 4D SB2 when i sold my EPA-100 about 5 years ago, but everything turned up not as i expected, so i ended up using different cartridges on Reed arm. I remember i was happy with Garrott P77.