They did make a few errors, and their work was criticised for being overlit compared with CBS Digital, resulting in the rest of the series being brought in-house.
I don't think that was completely fair personally - 'Q Who?' looks incredible. It probably just needed someone from CBS to keep a tighter watch on them to ensure quality control.
It's absolutely completely fair, but it s also very predictable.
During TNG's especially early years, the work on episodes was done by either Rob Legato or Dan Curry. You could always see the visible difference in the presentation of original SFX shots. As the amount of material (nt to mention the amount of Trek produced increased) they expanded the staff so that Curry and Legato supervised additional teams, versus by the ones doing it themselves.
Legato's work is sharper, and featured a far larger range of color. Curry's work was softer and was over lite. You can also see this difference comparing DS9's first season to the remaining seasons as Legato left after season one.
Once it was announced that Curry was in charge of that season, I knew without question that the season would bear his style versus the style of that particular episode.
You mentioned that Q-Who look good to you. Well it doesn't suffer the extreme change because Q-Who was a Curry episode originally. So the look did match his original style. Compare that to the SD and remastered version of "The Child" a Legato episode, and the difference is vey significant. The shots lose all of Legato's style (minus of course the actual design of the shots).
Now of course to be far. The revers is also true. The remaster for seasons 1,3-7, really didn't try and match the visual style of the episodes Curry was in charge of. They tended to match Legato's style and make the shows look more unified in style. That technically isn't fair to Curry. And didn't represent the original broadcast work.
Personally of course, since I never cared for Curry's soft focus and over lite work (Nothing against his layout of shots and I think he did wonders with creative and cheap solutions to get shots done on budget and time), I was very pleased that his lighting style wasn't mimicked in his episodes of the rest of the seasons.