I do not know if it is client or server side but recording quality is really bad, especially for the video frame and audio encoding.
There is a world between what you see/hear live and the exported recording :-(
We are using a 720p video feed and audio from a mixing console (hand and tie mics) so the diference from live to export is really bad :-(
So far I capture the slides wit Lync the I add audio and video into a Premiere Pro timeline. this is the only way as Lync does not produce "good enough" quality recordings :-(