Just beat today. 100% Items. 14.5 hours (over 20 total on Switch... guess I died A LOT). So much fun. I can now safely say, this is my game of the year.
My 2nd ever 2D Metroid after Samus Returns. Such a phenomenal experience.
I will not be doing Hard mode though lol. Normal was hard enough for this guy.

Only negative things I can say are:
I wish the loading times between areas were shorter
I wish the music was more memorable

Other than that, I've loved every second of this game. As a relatively new fan of this series, please try/buy this game. I'm very glad I didn't have to wait 19 years and hope it doesn't take that long this time :P.

Now after replaying Super Metroid I have decided that I consider Metroid Dread to be the better game. It has just way more fluent movement and because of that is more fun to me.

Both games excel with their atmosphere but Super Metroid has a more memorable soundtrack.

Metroid Dread - 10/10

Super Metroid - 9.5/10

Metroid: Samus Returns - 8.5/10

Metroid (the original on NSO) - 5/10 (it aged terribly)

That are all Metroid games I have played. Metroid Dread is one of the best Switch games so far.

This game really blew away my expectations; going in I expected a solid but not amazing experience, now I rank it as my #8 top game on Switch.

I guess I expected more tedious wandering around figuring out where to go next, whereas in reality it was so tightly designed there was hardly any downtime. I also thought that the EMMI might start off cool but get annoying fast, but in actual fact they almost never frustrated me and remain genuinely intimidating and fun to escape and defeat throughout.

As awesome as Super Metroid is,  I even find Fusion and Zero Mission to be better games. 

After beating Dread I decided to go back and play Super Metroid again, and it was jarring how slow it plays compared to Dread.  Plus wall jumping is MUCH easier in Dread. I agree that the music is more memorable in Super, but so far that might be the only clear advantage it has.  I'll keep going on my Super Metroid game and see which one I prefer in the end, but its spot as my favorite Metroid is in real jeopardy now.

It's almost a miracle how perfect they got Samus's portrayal in this game.

They manage to convey so much with her behaviour and body language, or with just her eyes through the visor. Having her speak only once, in Chozo, with a line that oozes badass confidence, was a masterstroke too.

Ever since Other M I've been worried about how future new entries in the franchise would handle her character, but Dread puts almost all those concerns to rest.

Just wanted to point out that, while what you're saying is true, wall jumping is very limited in Dread compared to Super, similarly to Fusion and Samus Returns. In Super (and Zero Mission too) you can infinitely wall jump on a single wall, something you can't do in the others unless maybe if you do some crazy speedrunning maneuvers.

Nintendo have released a demo of the game on the eshop

https://nintendoeverything.com/metroid-dread-demo-released-on-the-switch-eshop/

That's a weird timing. 

Y'know what... I actually think that was a good idea and wish more companies would do this!

The people who were in to this game already from the first trailer were going to buy it almost Day 1, no matter what. So there was no need for a demo then, because the main audience they were selling to was already firmly convinced and on board.

Now that the game has been out for nearly 3 weeks, it has sold extremely well, and the reviews are glowing, there are going to be a lot of people who were borderline, who wanted to give the game a shot but were unsure, now they don't have to fork over $60 for something that they may or may not enjoy. The demo + all the word of mouth about the game post-release will give them a much better perspective and idea than they would have had if the demo came out pre-release.