Granted, the Equinox is a 40/357sig P229, but close enough.
I'm going to tell you right now, any of the Sig Elite Stainless Steel variants are going to be incredibly hard to find. I've seen a few Equinox handguns here and there but they're becoming harder to find as well.
-fiberoptic front night sight, amazingly bright in the sun
-cool looking grips, laminate but I think they look the best of all Sig grips
-nickel coated levers and screws, also very cool looking
Elite Stainless has:
-SRT trigger, big feature for trigger reset advocates like myself
-wood grips of which I am not a huge fan (I plan on getting Equinox grips on my P220 Stainless whenever it comes in)
-beavertail frame, this may or may not be up your alley
As so many times on this site it seems this is another case of splitting hairs. Between the two, form and function are 95% identical, so really it's just a question of which one you think looks better. Personally, I like the stainless beavertail frame, but good luck finding one if you decide to go this route.