Good question! I think they’re both comparable in terms of quality, but the AKG’s are a little more neutral/treble-focused, whereas the Bose model has more pleasing bass.
More troubling is that Bose seems to have largely kicked the SoundTrue Ultra to the curb in favor of more focus on their noise cancelling models and their new head speaker thing. They’ve been discontinued and kicked off of their web site in favor of newer models. So if they were something you’re interested in, and you’ve found a good deal on a pair, don’t sleep on it!