I own a Fast Fire lll and a J Point and have one mounted on my FA .475 and a FA .454.
I have been considering an Ultra Dot. I know the Ultra has many brightness settings while the FF lll has only 3 settings. I like the smallness of the ones I have.

What are, if any, the advantages of the Ultra over the other types that I already have?

Bad weather gets on the lenses faster with the type you are using IMHO. The tube type seems to keep rain and snow conditions down to a minimum.

FAH,

You will probably also notice a difference in speed of picking up the dot. Tube types and actual scopes are pretty fast from the get go. The micro dots take more practice to find quickly. Where scopes can get slow is on high magnification, where the placement of your head/eye can become an issue. Should not see this with a zero magnification tubed dot.

FWIW, I am running a Trijicon RMR on a S&W 625, and am getting pretty speedy from leather with it. Practice. But, it is the auto/manual adjustment model, and being able to really fine tune the dot brightness is very nice. I have been through about 4 or 5 different brands of micro red dots over the years, and this ability to dial down the dot has been an eye opener for me. Whether you go tube or different micro, it is certainly a worth while consideration.

Craig