I have the glass Big Mouth bubbler and I've used it three times with no issues. Instead of the harness, I went and purchased a half sized milk crate for $10 (
http://www.containerstore.com/shop?productId=10000531&N=&Ntt=crate) and it fits perfectly in it and I use that to move it around, even when it's empty. This way, if it does break the milk crate will contain the large shards that can slice your leg open (it has happened to other home brewers using standard glass carboys) and I feel the milk crate is a lot tougher.
With that said: Racking from it is no big deal, unscrew the large top and insert the siphon and clip it to the side of the Big Mouth, my auto siphon has a clip on it. It's actually easier with the siphon in a big mouth because since you are so close to the side of it, you can see how far down to go before it hits the trub where as with a glass carboy, the siphon is in the center and you have to do a lot of guessing. I usually put a wedge under one side of it to allow all the beer to go towards the siphon.
The Big Mouth bubbler glass is not thin all around, there are defects in the glass (possibly from air pockets) that cause certain parts of the bubbler to be thinner than the rest, the QA on these things are non existing. I have also gotten some standard Glass carboys with the same issue, these aren't made like they used to be made years ago since plastic has been taking over.
I've since moved onto a Stainless Steel conical from SS Brewtech. The fear of dropping one of those glass carboys as I was moving them, even just cleaning them, gave me nightmares after reading so many posts of people being rushed to an ER to get their legs stapled/stiched closed. I remember one member stating that they were simply moving a standard glass carboy that was full and it just broke from the pressure of liquid being in it and they were rushed to the ER. I figured that since I'm in this hobby for the long haul, saving up $350 for a stainless steel conical that will probably outlast me plus give me the comfort that it won't shatter and risk my limbs was a much better choice for me. I didn't want to switch to plastic for a number of reasons that I won't go into here since there are so many threads that go into the pro's and Con's of better bottles.
The Big mouth bubbler is a great fermenter but could be improved on such as getting better QA on it. Also, the cap that screws on is pretty flimsy, very cheap feeling, seems brittle. Other than that, it works well if you take caution with it as you should with any glass carboy.
I would highly suggest you ditch the straps and use that half milk crate I linked too. The straps are OK but they do put pressure on areas of the glass that normally would never have pressure on it. The bottom and the tops of these things are seriously thick, the walls of them for some reason is where the thin areas are. Using the crate keeps pressure evenly distributed to the bottom and also will protect you from large flying shards of glass if it does break.