Layer height can be anything you want, though generally you wouldn't layers thicker than 75% of the extrusion width.

I am fairly new at this 3D printing but here is my take.

90 percent of the stuff I print I am more interrested in speed than detail.

I have my nozzle diameter set at 0.45
I read somewhere that the actual size of the nozzle is 0.48

I then set extrusion width to auto and primary layer height to 0.45

With these settings it take half the time to print a model and
it still looks great to me.
If you do a acetone vapor bath like I do on many parts its even less important
how good the layers look.

According the manual and machine specs the 1.0 and 1.0A both have a .40 nozzle. That being the case your layer height should never exceed .35 on a .40 nozzle. If it does there is not enough surface area being bonded to assure proper strength. Your prints may look OK but will never be as strong as a print that is printed properly. There are some undocumented rules about printing such as the width to height ratio that should be followed. Unfortunately as I said it is hard to find a #D printing rule book so you really just have to dig through the 100's of sites for information. Back when i started and the rules where being established there where only a few sites and information was much easier to find.

90 percent of the stuff I print I am more interrested in speed than detail.

I have my nozzle diameter set at 0.45
I read somewhere that the actual size of the nozzle is 0.48

I then set extrusion width to auto and primary layer height to 0.45

With these settings it take half the time to print a model and
it still looks great to me.
If you do a acetone vapor bath like I do on many parts its even less important
how good the layers look.

As for my default extrusion width, if I want to print at a height of .2mm, would I make my extrusion width of .24 (.02 * 1.2) or would I just leave it at a static number for all my prints regardless of height (say .4mm)?

Sorry for the newb questions, the more I learn, the more I realize just how much I don't know

Quick question.

I am using simplify3d and noticed for the Da Vinci they have the default extrusion width set to .4mm. When trying to print something at 4mm, I had to use the 'auto' default extrusion width which set it to .48mm. Since then I did some research and understand your extrusion width needs to be 1.2 times your layer height. As I'm still trying to learn/understand all of this, does that mean I would need to change my extrusion width to different values when printing .4mm, .3mm and .2mm (or would I just leave it a constant .48mm)?

Any feedback or tips would be appreciated.

First an foremost your printer has a .4mm nozzle. That means you csn never print a layer height that exceeds .35. That is why after market hot ends come with a variety of nozzle sizes. You can only or should only print a max layer height that is no larger than .05 of your given nozzle size. Of course you can always print smaller. Extrusion width should be correct if you stick to that rule.

I am using simplify3d and noticed for the Da Vinci they have the default extrusion width set to .4mm. When trying to print something at 4mm, I had to use the 'auto' default extrusion width which set it to .48mm. Since then I did some research and understand your extrusion width needs to be 1.2 times your layer height. As I'm still trying to learn/understand all of this, does that mean I would need to change my extrusion width to different values when printing .4mm, .3mm and .2mm (or would I just leave it a constant .48mm)?

Any feedback or tips would be appreciated.