Since most answers are complete shit or seemingly biased... no not yet. Wait for a sale
-If you're a fan: it is not as good not even in the same galaxy of how good the original ME are
-the animations deserve the hate they are getting as they are that poor. I can literally do better with free software granted it would take time though. PS alien models are copypasta. Reusing resources is not a bad thing but should be made less obvious to the perceptive eye
-still buggy in many minor ways. nothing game breaking mechanically speaking except one mission that may or may not by patched yet... I am unsure so will not post
-the game demands way to much performance wise to get the same graphic the older ME games did
-mp in MEA is like in ME3 but better seems the opinion of many
-mp has optional microtransactions
-FPS is not consistent (across all systems)
-the single player lets you change powers setups and "profiles" as you please willy nilly
-not opinion but fact... the writing is notably poor/corny in some parts
-the single player has significantly less tension but that's due in part of the premise of exploring and all that. Regardless even so the game is slightly "pussified" as some might say regarding the feeling it presents
-MEA requires bloatware known as origin to run (if pc)
$44 for PC on here https://www.greenmangaming.com/games/mass-effect-andromeda/
It's stated on the official website (see the Andromeda Initiative training briefing, at https://www.masseffect.com/andromeda-initiative/training-hub/welcome) that the Initiative was "founded" in 2176 (the year of the Skyllian Blitz), actually launching in 2185 (the year of the events of Mass Effect 2). The briefing also states the flight time will be 600 years.
This is just an educated guess on my part but the reason the initial date was 3/21/17 is because Amazon posted that the book "The Art of Mass Effect Andromeda" was scheduled for release on that date "to coincide with the game's release" (see https://www.amazon.ca/Art-Mass-Effect-Andromeda/dp/1506700756/ref=sr_1_1?ie=UTF8&qid=1482236512&sr=8-1&keywords=the+art+of+mass+effect+andromeda). The fan community took that to mean that the game was then going to be released on that date. The official date still hasn't been announced but EA/BW still have it slated for Spring 2017. I would assume that dates of 12/31/17 are exactly what you said: retailers don't have a date so they put the last day of the year in which the game will be released.
40 https://www.g2a.com/mass-effect-andromeda-origin-cd-key-preorder-global.html 35 which is about what it's worth. Good game but holy shit does it have flaws https://www.greenmangaming.com/games/mass-effect-andromeda/
So I bought it off of Origin, then used my VPN and the date changed to 21st.
I even bought it using queen faces.
The VPN I use is a paid for one but is very VERY worth the price, it also works on a certain streaming service that I won't name
ExpressVPN is who I use