I certainly don't agree that Manticore was rushed to market. Their chief engineer says they worked 3 years developing this machine in a recent Youtube video.
Now I ordered a Deus II and returned it last week after my own evaluation of the machine. Here's my own conclusions as a software engineer of 40 years, who has worked with many highly technical subjects, manuals, and evaluations of computers and software.
I have several problems with this machine, manual and headphones.
1) it is too complex and complicated to really understand for typical user IMO
2) the manual is lacking IMO.
3) the charger connection position on coil is flimsy and could be easy to reverse. That could damage the coil according to what I read.
4) the multi-use, multi-function buttons on control pad add complexity and confusion for user.
5) the headphones barely fit my head and I'm not so sure they would not fall off in the field.
6) the control knob or puck on headphones is redundant and makes zero sense to me when you are sold a control panel that has all this info. And yes, I know it can come off and be used without control panel. Again - makes no sense to me at all.
7) requires a flimsy antenna wire IMO to be installed before you can use water hunting. So much for 'wireless' claim. Guys that salt water hunt all the time are saying that antenna wire is rusting on them.
I was all sold on this machine, the hype, the more depth, all those gold coins supposedly being found until I got the machine and determined I wasn't going to use this machine for the above stated reasons.
One more thing, they added two more levels of complexity for the user - in making coil and headphones wireless. Now you have two more devices to remember to charge, two more batteries that can go bad on you, and two more reasons to have to return machine for battery replacement. I am frankly sorry to hear that Minelab followed suit with the Manticore's wireless coil and headphones.
I know those using Deus II will disagree. That's great! I not here for a 'tastes great, less filling' argument. But I hope some trying to make the decision will consider these things and realize this machine could have a huge learning curve for them - if they want to use anything but standard programs. Only time will tell how Manticore will fare against the Deus II. I can say this now that I have one, the Equinox 800 is a sturdier machine than Deus II (IMO) and I can walk right into water to use it without having to add a wire antenna, and the headphones will still work just fine.
Where I am at now, I need simplicity. That works for me.
The above is strictly my opinion. You may find the Deus II the machine of your dreams. I did not - enough said.
Adding some levity to this post, I guess the engineers at these companies must feel like this guy -
I read your review and thought well you weren't sold on the machine.
I bought one-and reread your review.
I'm not tech savvy, so besides turning on the machines it takes me a good long while to figure the buttons/programs out.
(School of hard knocks-is a way of my learnings)
Manual/instruction pamphlet-yup needs a simpler way of explaining things.
Well I can reread something over and over again-and it just doesn't explain it well.
Like getting into the XY screen and having it stay there.
Headphones-well we must have the same barber/or lack of hair to catch those things in the right spot and make them stay.
Nope I like the cuff type-so I ordered up the Deus wireless-spring/fall weather my ears are snuggly, and it blocks out the wind.
Now the charger for the coil-easy-wide goes with wide/narrow goes with narrow. Can't see how that could be an issue.
Now the charging cable to the pad, have to align it the right way, then screw it in. (not a winner there)
Charging port on the headphones-same thing it's in a cave-I fumble around trying to find the right position to plug it in
Now it's sturdy, coil is tight, wand doesn't flop, and it's light.
Turn on and go-now that it pretty basic.
General program-simple-learn it-then move on.
Now the actual machine in the field.
I've only done sites that I have been to multiple times. Some of these heavy iron patches were to the point where no non-ferrous targets were retrieved after a few hunts.
All close by-no problem with time or $$$ visiting.
Just lets try this or that to suck out another target.
Some of these places have had me hitting them for 6-8yrs.
The general program-multiple target recoveries. Some sites were like "Did I even detect this site?"
Separation in heavy iron target patch is great, way better than the Deus 1
80% less dug iron-and called it on 10% that it would-but just had to see.
When it locked onto a # it stayed at that ID # even when out of the hole.
Now I dug a few 12" targets, and the ID was spot on from start to finish.
I took a few pictures showing depth, and one site had a high voltage electric fence bleed ticking the whole time at the site.
(I didn't want to start messing with the controls out in the field)
A simple small pack rivet between large and small nails-and it called it.
I was debating on what machine to get-money wasn't an issue as I did a scrap clean up and what ever machine was free basically.
Deas ll & Wireless Headphones $2600.00 Can. I already had the pinpointer. (Which have a discrimination feature)
What I'm driving at is the Nox 800 coil ear problems (buy ear stiffeners) WTF!
Controls leaking-another issue
Just dying-say what?
I play baseball in life and that was a strike 3-it's out.
Might have a brain-but what good is it if the lacking body that drives it fails.
Batteries-

My Deus 1 is still running strong after 5 yrs and I've had no issues with them.
So I give them a thumbs up-no problem
For a long hunt-it still gave me plenty of charged space.
As for the Puck-a person basically has a back up plan if the other has an issue, I might order another coil (11") use the Deus 1 stem and have another machine on the cheap. (Gee might I might invite somebody to go detecting with me)
Slap! Ok that was a frightening thought-last invite lost me a 250 acre permission.
But I digress.....
Seriously going from Whites-the Minelab Explorer series-CTX3030-Deus 1-Deus 11
Each company switch was a learning process.
It took time-I was still learning the Deus 1
I can't wrap my head around how some folks just pick it up and go- meaning like 40 machines in 10 yrs.

I feel it takes 1000 hrs to really know a machine-a dig or pass-and never doubting that decision.
That's my newbie take on the Deus ll-winter knocked early this year-so it might be a sort the finds out type of winter.