In the grand scheme of things, Bentley has done next to nothing in terms of music for the Sonic franchise. Just taking a look at the games, and ignoring the idiot fans and quasi-official remix CDs only found online and in obscure stores (i.e. those who obsess over everything BUT the games) and all you've got is Shadow the Hedgehog, Sonic Rivals and the 2006 Sonic the Hedgehog.
Shadow had three Remix Factory remixes (aka original songs from other people). Rivals had a handful of tunes from them, none of which seem to be too notable as a Google search came up with one to two examples and even a visit to a few of Bentley's discogs cite the Rivals series but gives no specific tracks.
The ONE song that gets any mention in all of his bios/discogs is Dreams of an Absolution. Too bad it is featured in the worst Sonic game ever created and represents the most universally hated Sonic character. Hell, even Bentley's Last FM channel is clogged with remix after remix of the same song. How one note can this guy get:
http://www.last.fm/music/Lee+Brotherton+(Remix+Factory)/+charts?rangetype=week&subtype=tracks
Oh wait, he also did that song So Much More for SASASR. Possibly his last piece of work for SEGA. Of course, this song is nearly invisible in the game, only heard if one completes all cups within a difficulty over the credits (easily skipped with the push of a button) or is briefly heard when a cup is won. Whoop-de-shit.
So in summation: Bentley has done a handful of remixes of others music and two original songs. Both original songs are obscure within their respective games either due to the game being shit and hated ('06) or the song being hidden enough to be ignored (SASASR).
Now if we're talking about musicians from the past ten years who truly represent the Sonic franchise and fit with the feel of the games, we've got Richard Jacques, Jun Senoue, Crush 40, Tomoya Ohtani, Kenichi Tokoi, Mariko Nanba and Fumie Kumatani. Those folks have done "So Much More" than Bentley ever has, they just don't prance around and take about a thousand photos of themselves mugging for the cameras. Thats the only thing that has helped Bentley push the lie that he means something to the Sonic franchise. Post enough photos and videos of yourself next to the Sonic logo and play the same two damn songs and most idiots will think you made an impact on the franchise.