Adding the $.02 from a newbie who's been watching every video from both sources and reading as much as possible to gain knowledge (before crashing my first plane), I've got the following opinion:
The Joshes are entertaining and bring a lot of life to the videos. The banter, sarcasm, combination of expert and (former) newbie, and great production values make their reviews some of the best I've seen. Do some of the reviews appear like commercials for their sponsors? Yes, but they tell you numerous times in each video who paid for the gear so at least they're being somewhat transparent about it. More critical reviews would be welcome.
Watching Bruce is incredibly informative, but it can be like sitting in a college lecture hall with a professor who doesn't slow down enough for you to take good notes. It can be information overload, at least for a noob like me. I like the critical (sometimes over-critical?) reviews, giving the viewer as much information as possible to make an informed decision. However, when I start one of his videos and see it's 15 minutes long I consider bailing on it and watching something else unless it really interests me.
By contrast, I could sit through a 15+ minute FliteTest video pretty easily.
Find a way to combine the best of both worlds and you'd really have something!