I'll come right out and say it...I never really cared much for the Deathwatch Space Marines.
I always thought collecting the best Astartes from each chapter to make a greater elite force was kind of cheating in a way.
Perhaps it comes from my own background in international martial arts competition where big money sponsors would cherry pick the top talent across the country to create elite competition teams. However, my dojo had a competition team that went head to head with some of the best sponsored teams with all of my teammates coming from a single school.
It is probably this impression that gave me a slightly disinterested stance regarding the Deathwatch while I was gung-ho for super cool chapters (my love for Blood Angels, Thousand Sons Legion, Grey Knights, and the Minotaurs chapters knows no bounds).
Then the new Deathwatch Codex and models arrived and holy cow was I impressed. Not only are the models stunningly beautiful, the Codex itself is a masterpiece that reminds me a lot of the 5th edition Grey Knights codex in its tactical flexibility (I DO really miss that 5th edition Grey Knights codex. Not for it's inherent power, but that it allowed such an amazing variety of army building choices that had really good synergy).
What also really sold me on the Deathwatch Codex was "The Beast Arises" series of books from Black Library. This series was a huge catalyst for me to start looking at the 'boys in black'. Their unique weaponry like the Infernus Heavy Bolter, Frag Cannon (my Furioso Dreadnought wants his weapon back!), and the super cool Corvus Blackstar which is arguably the best looking flyer in all of Warhammer.
With that said, I took a plunge and heavily invested in multiple cans of Chaos Black spray. I've only completed a few models and I'm steadily working through the Deathwatch Overkill box game and recently purchased a Deathwatch Kill Team squad. The first model I completed was the Watch Master.