I would definitely recommend the Nemesis. I bought a a Dingo because I thought I would never get my hands on a Nemesis, now it sits on the counter. It is a nice little mod but I was disappointed by a few things. The extensions fit poorly and the finish does not match very well(not an issue with the roller, of course). The fittings on the base mod were almost seamless, I can't even see the line between the top cap and tube. The switch on mine is crooked, I did not notice it at first but now it really bugs me. It works great and looks pretty good in it's original 18350 mode. The switch assembly is quite frankly annoying and bothersome as compared to the Nemesis. The locking feature on the Roller is also annoying compared to the Nemesis. If the switch was just a tad beefier, knurled, and did not rotate past the on/off positions, I would enjoy it a lot more. The battery spring on the Roller is annoying, as compared to the threaded switch on the Nemesis. The center pin adjustment on the Roller is annoying, compared to the knurled thumb screw on the Nemesis. The center pin on the Roller is too loose and adjusts itself unless fully tightened. I just really find the Roller to be too fiddly. You need tools to take it apart, let alone make a simple center pin adjustment. The Nemesis is downright beautiful, and is easily fully disassembled by hand. It is so simple to break it down for a quick bath, including the switch. In my opinion, there is no decision to be made here. Don't get me wrong, the Roller is very solid and somewhat rugged by design. You won't cringe as badly when your friend swipes your Roller off the table and onto the concrete patio. If you decide to rely on a Roller, be certain to always carry a tool to adjust the center pin. All it takes is an inadvertent twist of your atomizer and your center pin can tighten too far and create a loose connection. I have many other negative points concerning the Roller in regards to the Nemesis, but I am a very particular person.
Bottom line: you won't be disappointed with you Roller until you get a Nemesis.