I have a blue/orange Misfit and I love it for dry and burned up lanes. I will say that it is a little stronger than I thought it would be, but it was a pleasant surprise. I make sure to keep it polished and couldn't be happier with it.

I think the answer depends on the ball and the bowler. I throw on the harder side of things and I used to throw a dull ball on dry lanes....it was a urethane Sumo. I kept it on the duller side to get some traction in the heads to try and increase carry. If I was throwing a plastic ball on dryer lanes, I would probably want it on the duller side. But if wanted to throw something stronger, I would probably want it polished to help increase the skid of it and allow the stronger cover to pick up later. I don't think there is one right or wrong answer here, it will depend on the bowler (how they throw the ball), and the ball choice (the type of cover, strength of core).

It really depends on what you mean by dry.  If you mean a short pattern with stripped back ends where the ball jumps off the end of the oil a dull ball might be of some use.  Likewise if you are talking about a wet dry wall with no oil outside, but plenty in the middle. 

On the other hand if you are talking about lanes that have had a lot of play or where you are bowling second shift so that the heads have blown up, then a shiny ball makes total sense. 

I answered this way because so many times I hear guys talk about how dry the lanes are as they stubbornly refuse to move a bit inside second arrow to find the high volume of oil that is still there to be found. 

OP: define "dry"

Polished/shined surfaces respond faster to friction.

I prefer to knock the shine off my drier lane equipment 2000/4000 so it will pick up a little earlier but will not jump as hard off the friction.

Bowler style is also a factor.  The deeper I can get on the lane the better.