I've just got one to replace my Halo, I mainly use HM machines but unfortunately Roman doesn't make a fully adjustable machine (stroke and give) and I like to have at least one in my arsenal mainly as an all round back up.
Didn't want to buy another Hyper v3 as each one seems to be a completely different machine, or Halo/FK as being in the U.K. turn around time for these if anything goes wrong could be weeks which is not what I want.
So when I saw that I can buy all the spares and tools from suppliers here in the U.K. plus an extensive PDF manual I thought that a dragonfly X2 could be the answer.

Its a lot lighter than what I'm used to, HM machines feel more substantial if that makes sense but that's not a problem. Stroke is altered very easy although more difficult if the machine is already set up. Give is spot on if needed, rock hard to very soft- what more do you want.
It has only a very slight vibration and is almost silent.
Ive done a few tattoos with it, mainly black and grey and as Casey says it's fantastic for those soft effects. Switch the stroke up and wind the give in and it will bray solid black in with an 11 mag no problem.
Lining seems totally fine but only tried it on and easy bit of skin.
Ive yet to do any colour work with it but can't see there being any problems there.

So it's a great little machine. Better than my halo and my hyper v3. Way better in fact.