This is a very interesting episode--one that is well worth seeing. What I particularly like was seeing T'Pol meeting...T'Pol! Overall, it's well written and well done.
This episode hurts my brain. The fact that this season takes place in the Expanse (which doesn't abide by the normal laws of gravity, time, etc.) allows the writers a bit of free reign regarding normal plot holes and time paradoxes. They can just blame it all on the Expanse; on one hand it's a bit annoying but on the other it's cool that they can think outside the box a bit.
Taking all that into consideration, I kind of liked this episode. I enjoyed how every character got to see their futures and how some seem to be planning on changing their outlook because of it (i.e. Reed or T'Pol). I also thought Blalock did an admirable job portraying T'Pol as an elderly Vulcan. it was smart of the director to leave her in a dark room so we couldn't really see the terrible prosthetics and makeup job I'm assuming they used for this character.
We also got to further the plot more by arriving at Degra's meeting place, an added bonus. So, what did happen to the other Enterprise? Were they destroyed? Did they fade away like a Back to the Future movie? I liked that we never find out for sure.
"E2" is a flawed episode, where the only explanation for the holes in the screenplay is the Expanse, where the laws of physics and time are different. T'Pol alive and the duplicate Enterprise together with the original T'Pol and Enterprise are absolutely incoherent and I did not like this unnecessary and forgettable episode. My vote is six.
Title (Brazil): "Enterprise 2"