Are Dust Covers a MUST

I use a dust cover on my Immedia turntable for two reasons: to keep dust off, and perhaps more importantly, to keep people's hands off.
Joseph

Dust covers not only keep the dust out but also keep wandering hands away. Many of my customers regretted not having a dust cover on when they lost an expensive stylus to cleaning ladies, kids, pets, or even their own loose sweaters.
I don't recommend keeping the dust cover on when playing, however, as its resonance will screw up the sound (the cartridge picks it up).
Disclaimer: I sell dust covers.
Vinh Vu
Gingko Audio

I think you are asking if one should leave the dust cover on during play or not. I have owned a MMF 7 in the past and never liked the sound with the dust cover on, flipped up or not. The MMF 7 had hinges that allowed for easy lift off of the dust cover. I'd remove it while the table was in use and replace it when I was done.

IMO, it is not a must have for maximum vinyl enjoyment. However, as others have posted there are many excellent reasons to have one. Currently I have no issues with hands of any kind and I haven't had a dust cover for several years. I do carefully use swiffers and microfiber cloths pretty regularly.