🚀 go-pugleaf

I'm in the process of building a large aperture Dobsonian.  I am
at the point where a decision must be made as to the optical
company from which I should purchase the mirror.  I am considering
four companies, Galaxy Optics, D & G Optical, Pegasus Optics, and
Handmade Telescopes, all of which sell a 20 inch mirror for about
$2000.  My question is does anyone have any experience with these
companies, especially where mirror quality is concerned?

In the same vein, this telescope is an open truss design and I have
read that one's body heat will seriously degrade image quality. 
I have been considering the use of bubble wrap as a shroud.  Is
this feasible?  Is it practical?  Will I still need a black cloth
shroud to eliminate stray light?

In their advertisements Astro-Physics published testimonial letters
describing Enke's division as being easily observed through their
6" apochromatic Starfire telescope.  Is this possible?  Will I be
able to resolve Enke's division with my 20" f/5 Dobsonian?