formal evening dress: vest or no?

[CMcG]

<snip>
In my opinion the PC should always be worn with a waistcoat. I just don't think it looks "finished" without one.

When I purchased my Prince Charlie, it came with the three button waistcoat, <snip>

<snip>
For the PC, I think the low-cut, 3-button waistcoat with bow tie is better.

I know there is some precedent for the PC and belt/waistplate look, but I personally do not care for it. I think for formal dress the PC should be worn with a black bow-tie and a 3-button waistcoat. <snip>

<snip>
If you are discussing a Prince Charlie jacket specifically, as these typically are sold as a unit with a 3-button waistcoat, that is the first recommendation. Though many of the pictures posted show a PC worn with a belt and waistplate (sans vest), I personally don't think this looks as nice.

As for the Sherrifmuir doublet...

There seems to be lot of favour for the PC with 3 button waistcoat and mixed reviews of other looks...

I chose the PC as my main example because of its prevalence but in my wardrobe lies a Spencer jacket, which I intend to wear as a PC replacement. That's why I originally asked about the broader spectrum of (what seem to me) related jackets: Prince Charlie, Brian Boru, Regulation, Spencer, Eton, and Mess. Does the same apply to the other jackets?

Apologies for the inclusion of the Sheriffmuir in the OP, which Matt commented on and made me realize my mistake. I have edited it because I meant Regulation (more similar to a PC):

[Zardoz]

My primary formalwear is a Spenser jacket and 3 button vest.