Not judging his positional ability, I am judging his technical ability though. As I said above, I know the sorts of positions he enjoys and I can't see how it's going to work with him out wide in Rodger's system. He was more anonymous than Downing yesterday because he hasn't the ability to run at his man, therefore the attacks stopped dead when it got to him - he had to turn back. When it was Suarez and Johnson linking up on that side, it looked much better.
He isn't an out and out winger, but he's quick, can cross, and technically strong. It's the wingbacks who should be bombing on and hitting the byline, not Borini, and it's their overlaps that are relied upon to create space and channels for the likes of Borini. Unfortunately we didn't have Enrique yesterday, who offers that natural width on the left, and Johnson naturally cut into Borini's path, forcing him out wide into a position he's not great at. Additionally, on the right, Kelly didn't offer near enough adventure down the right, forcing Downing out there too with no overlapping backup.
You're right in that he isn't a winger, but usually that shouldn't be a problem. It was yesterday because our fullbacks weren't in the game as we'd have liked.