Dust cover up or down?

Dust cover off . It states it in the manual for my tt. 

I have a Sota Comet I bought used and the dust cover is more or less an afterthought, and looks like it, something they started making because there was a demand for it. There are holes for hinges in the back of the plinth, but it's clearly never had hinges on it. I take the cover off and set it aside while playing records.

My rega RP8 has a surround support and dust cover... After 3 years I removed everything bar the Skeleton inner. Sounds much better... So was looking for large perspex cover for dust protection when not used... But just ordered a michell uni which is sleek and minimal

Will work for a lot of smaller decks like Kumzi rega michell

VPI Classic, custom cover fully off when playing, back on when not.

Pro-ject debut III, cover with hinges, up when playing, down when not.

It really has a lot to do with the design and quality of the TT and cart.

I've used my Linn LP12 since 1984 WITH the dustcover on. I LOVE the dustcover!—it allows me to leave records on the platter overnight. And I cannot hear any sonic problems its causes –  up or down.  

herb