The S3/5 does work very nicely close to a rear wall. Its limited bass and lack of port gives a very nice bass response even when placed directly on the wall. I'm not sure you can beat it. I'm not sure if the harbeth is significantly better for the money but between the two I'm sure you'll find a winner.
Of course imaging dissapears as the rear wall gets close, which is too bad.
Of course imaging dissapears as the rear wall gets close, which is too bad.