With SLR video ever evolving it is easier and easier to get fantastic footage. I remember years ago saying that some camera manufacturers would make their video line obsolete – although that hasn't happened 100% you can see the evolution in their lines. For years, I used a couple dedicated video systems – Canon XHA1 & the JVC GY-HM100 and they were fantastic.
Now, I use my 7D on a customized rig and get fantastic results – the only issue is the annoyance of set up. Before the dedicated video rigs were self-contained control units with the sole intention to make great video. Now, I have to take out all the different modules needed to make great in-line work and have redundancy files needed for back-up (mostly in audio for audio sync & levels). The other draw back on SLR (for the 7D) is time allowance to capture in one take and it overheats if running too long - I could run the video cameras for hours in a single run.
However, you don't need all the modules - my rig is set up as an interview rig which can also run off tripod as a shoulder rig. The only addition I'll be making on this rig eventually is a teleprompter.
My rig works for me – it's set in as a modular system and only set up what I need. If I only need b-roll footage, then I can just run with the camera alone or go full set up for the more intensive work.