I owned the LS 100/KWA 100se combo. Its was nice but might be a little warm for the Harbeths. I would go with something less warm than the KWA 100se or the Pass (but the .8's are not as warm as the .5's right?). If you can stretch to try the KWA 150se, it is not as warm as the 100 and might be better for the SHL 5+. Or try AR.
