I was thinking it was time to quit lurking, participate and share my experiences.
I purchased my Rostock Max V2 kit last year after much research into and desire for a 3D printer that might meet my needs. In general, 3D printers have come a long way since I started becoming interested some 3 or so years ago. No longer do parts look like rough surfaced plastic blobs and any worthy printer can now produce functional and aesthetically pleasing parts.
I picked the Rostock Max V2 due to its print volume, price and because it is "different" than the mainstream, being a delta bot. I want to be able to print ever more larger parts and get into lost PLA metal casting, amongst other uses. To be honest, I wasn't sure what the quality of both printer or parts would be. I can enthusiastically say I am ecstatic about both. The kit quality is excellent and great value for money. It was a bit of a chore to build, taking more or less the requisite 20 hours and that again to "learn" how to get decent prints but I am happy I did build the kit as I now know what makes it tick and understand its limitations (few) and how I may be able to enhance build quality. The build instructions were clear and easy to understand. Out of the entire kit with a bazillion parts, I believe I was one single machine screw out (one left was too long so I shortened it) and I generally ended up with a few extras.
The hot end supplied is excellent. I have not had a single clog in over 4 months of printing. I can say that SeemeCNC's customer support is excellent. I noted that the PEEK insulator hot end sent with the kit was assembled so that the hot end of the hot end was kinked off at an angle and I thought that might impact prints if the bottom of the nozzle wouldn't be flat. After sending pictures of the issue, they replaced the hot end entirely and free of charge. I purchased another hot end to eventually do a dual extruder set-up and the quality of that one was just fine, straight as an arrow. I did purchase an E3D V6 hot end, but honestly, I haven't seen the need to change out the one from SeemeCNC. (I don't print ABS or Nylon as we have a parrot, so I am wary of noxious fumes. Printing in the above plastics does not lead to noticeable fumes of any kind by my sense of smell).
I plan to upgrade to magnetic coupled arms next as I did suffer a bit from the "delta arm blues." This was fixed by sanding the arms with wet and dry and then lubing up with (di-)lithium grease

The MatterControl MatterSlice supplied is perfectly adequate. It does have some "features" that irritate me but they can be generally worked around (It has a habit of deleting values from settings files, so exporting these occasionally is a good idea, so if you lose the settings, they can be re-imported). I did struggle slicing some parts so went all in and moved up to Simplify3D. I have also found that Repetier is an excellent tool also so I bounce between the three. I tries using Cura but that led to a few crashes (no harm done) but I did get it to successfully produce g code that ran without problem.
I can now print parts in PLA, Taulman T-Glase and Taulman PCTPE with relative ease. I have learnt that not all PLA filaments are equal, by a large margin, and that T-Glase is an absolute pig to work with until you find the magic Goldilocks settings and then makes for excellent robust prints (very "gooey" and flows poorly, despite hot temperatures).
Overall, I'm very happy with the purchase. It is gratifying to see that SeemeCNC's Rostock Max V2 has won "best kit" in a recent 3D printer shoot out (I forget which) and that is well deserved.
Jim