Here's some quick impressions:
Nicely made watch for the money. Looks more expensive than it is and with a ceramic insert, sapphire glass, decent movement and a functioning (albeit, barely) copy of the Glidelock it's a nice watch for those who don't mind the sub styling. The sapphire has AR which immediately made me realize how much I'd love to have that on my Sub. The caseback is lower than the Sub so the Marine Diver hugs the wrist much better which makes it a more comfortable watch.
Now the bad - the SEL's are slightly narrow and there's a tiny gap allowing them to shift from side to side. The SEL geometry is not quite as elegant as the Rolex's Sub and the bracelet line doesn't flow just as gracefully. The "glidelock" deserves a C-, it works but lacks any precision and the clasp itself takes a superhuman effort to open on my watch. The bracelet rattles, the Miyota 9015 rotor grinds like an old neglected ball bearing (probably needs a bit of lube). The bezel markings are just white paint so the question remains of how well they will age. The pearl on my sample is slightly off to one side, not by much but once you see it you can't unsee it. The downward pointing triangle is just a hair off the 12 o'clock mark. Accuracy-wise, I haven't been as lucky as many others who reported +- 2-3 seconds a day, mine looses 10 seconds over 24 hours, I haven't tried leaving it different positions to correct it yet. One more thing I detest (but it's not Tisell's fault and doesn't apply to my watch) is the stock Miyota date font, it's simply atrocious, so I opted for the no date watch.
One more thing that may drive an OCD person mad - the round and the rectangular markers on the differ from each other. The round ones have angled borders while the rectangular ones are flat, so they reflect light differently at different angles. Because of the AR coating on the crystal, the dial is more clearly visible than on the Sub, so the difference is pretty stark and stands out quite a bit. The other inconsistency is that the round markers have more lume (it's applied with a little "heap") while the rectangular ones have it applied flat and there's less of it. Not a dramatic difference but right after a quick flashlight blast the round markers are visibly brighter (the difference fades away after some time). Not huge cons, these, especially considering the price, but the watch would have been even better had all the markers been finished in the same style. But even having said that, the lume is glorious! I like to wear a watch to bed and so far this watch is just as good as my Sub in this department, it glows like a beast and lasts as long as the Rolex.
Overall - it's a functional and visually appealing watch (again, if you don't mind the Sub styling), great beater for summer and nice enough looking to wear to work. I'll most likely grab the blue variant as well.