Aviator owners: Aviator or D2 Delta?

MARQ Aviator may be slightly faster but the functionality and screen size are the same as the D2 series I believe. The MARQ looks vastly better on the wrist than any of the D2 if that is a factor.

Looks wise, Aviator wins. But a D2 (Delta or Charlie) is not a bad looking watch either. Aviation features wise, not a whole lot difference between the two watches (except for the Pulse OX, which is available in Delta PX). Aviator might be a tad bit faster, but hardly noticeable unless comparing side by side. GPS acquisition (in normal mode) is faster in D2 Delta (likely due to plastic casing) compared to the Aviator. I found an issue with the Altimeter sensitivity in the Aviator using the SW version 3.31. if you don't care too much about the looks, D2 Delta or Charlie will work, at least from the aviation features stand point. I am planning to make a review of the Aviator soon and will post on the forum.  

I am now thinking the Charlie or Delta would be the better buy for now. What about when the firmware is stable on the Aviator?

When I used to have D2 Bravo/Charlie, I only wore them while flying. Now, I wear the MARQ occasionally in rotation with my other watches though I can't quite back up Garmin's claims that it's a "luxury watch".

you are wearing it in rotation because it looks more premium, not due to functionality? 

Only wear it for functionality when I'm flying, otherwise prefer mechanical watches. But the MARQ is nice enough to wear every day (except with suits).

Any update to D2 Echo on the horizon?

I expect some of the issues be fixed. I am guessing (and hoping) that when they eventually release the D2 Echo, the new features would be ported to the Aviator.

Historically, D2 watches were introduced after the new iteration of the Fenix watches were released. I would expect to be the same case for D2 Echo.