I've got the CS300XS and I had been searching also. I decided on a pair of Reynaud Bliss (unheard) and placed an order. They should arrive in a couple of months. The other speakers I shortlisted were Audio Note K's, Harbeth Compact 7 and DeVore Super 8's. Not quite bookshelf size, but Harbeth and DeVore both have smaller speakers. This is probably not much help, but thought I would give you some ideas. BTW, I never heard any of these. There are no stereo shops anywhere near where I live. I am currently using the speakers in a 1957 Ampex console. For a while I used a pair of Dynaco A25s. I surpised how loud 15 watts was.
Mike