I have been smoking since I was tending the firebox for my dad long long ago. Let me help you with the MES understanding. First of all its my personal observations, which I think pretty highly of, but you may not. With an electric smoker you will not see a smoke ring, I have not seen one in 30+ years smoking with an electric smoker. I also have stick burners, pipe pits they are a very very dry smoker that makes that deep red smoke ring.
But don't dismay, you also have advantages with an electric. First and formost it doesn't require constant tending, which is a good thing so you can leave the door closed and prevent the cycling of the heating element. See a fire burner with dry heat will normally quickly recover from opening which is good for them because with that dry heat they require alot of moping and spritzing to help retain the moisture.
With an electric you seldom if ever need the water tray. Seriously its a drip pan in an electric. Since you don't have to worry about moisture, if you have a remote IT sensor, you can smoke while you sleep in bed tonight. The fire burners will catch cat naps all night tonight, while checking the temp and mopping and spritzing. Its a completely different smoking experience.
So don't worry about that smoke ring while you sleep tonite. I don't think I ever ever seen that TBS from an electric either, yes stick burners do, but I always used the vent to regulate the smoke. As you use the MES40 you'll see what I mean.
I usually rub with the basics, no mustard, but salt pepper, garlic and onion, and sometimes I use a bit of massaged in Lea & Perrins as my sticky glue. Sugar is great on ribs, but with a long smoke it really tends to burn, its my opinions again here.
As to using chips, I did it for alot of years, I still do upon occasion but I have one of those auxilary smoke generators that goes 12 to 18 hours. Its worth it. to sleep all night. Check out A-MAZ-N Products above in the sponsor section, BTW I think there is a 4th sale going on. I can only speak for myself, but they are good folks to deal with.
This is turning into a novel. Man if I can help, I can offer opinions anyway, let me know. I like my MES. I am sure your Brisket will be legendary today (already LOL)
Remember its about enjoying the smoke, and as a wise man says, Patience.
::EDIT:: ROFLMAO, I type too much, too slow!