I recently bought the Concert 8's for temporary use because I thought my ML Odysseys were starting to fail. I've used full range and monitors by Focal and was very happy with them but I've never owned any speaker that I was more impressed with than these eights. Detail is excellent and bass response is outstanding. I cant respond specifically to your question but either are probably good choices. All things being equal, my choice would be Jamo.
Jamo Concert VII's
Looking at a pair of excellent condition Jamo concert 7's for 300$ to add to my system as perhaps a rear channel or ??. I currently have a pair of old original Infinity kappa 8.0's feeding from a sunfire 300x2 amp that I just love. I have never set eyes on these Jamos but hear some good things about them. Any input on this pair would be appreciated by you experts out there. Thanks in advance.