Yes, definitely as far as the Commuter and Defender Series. Which I'm not all too sure they will produce a Defender considering none of the other HTC phones have one produced. All of that aside, OtterBox is your ultimate choice in thoroughly protecting your phone bar none!
I personally work in the construction industry. I know a few people in my line of work with the Defender series (iPhone). They all swear by it, I even know a guy who dropped his in a bucket of water. Pulled it out really fast, and not a damn leak (allegedly).
To answer your question YES, it's bulky. But in a I really don't need to worry about screwing up my phone way.. Adds a lot of peace of mind when your constantly exposing it to dust and moisture. The up side is OtterBox designs are made to be easily removed that way when your not at work you can let it breathe!