Mixing front and center

Get another pair of Focus 140s. Use one as a center and the other as a spare. 

I have been mixing center and mains brands for some time.  I currently run an old Dynaudio Audience 122C with Revel F208 mains.  Before that I had a Monitor Audio Bronze center.  Both were fine for movies.

The concern I have for you is that the Kef Q6 Meta may be quite warm in comparison to the Dynaudio especially if your sidewalls are far from the listening space.

Thank you for all the responses and sharing your knowledge  

i like the dynaudios for music (but need to power them better).     i want to add center for home theater. and reason i was thinking kef was bc i can get a discount on kef and seemed similar in specs as elliotnewbcombjr said. i didn't know if metal tweeter vs not and effect that will have  

idea of another focus is also interesting  

i did more more research and was thinking this overall   basically here is the story. i didn't have ability to use my system last 3 years and just moved into a house and took over the garage. build a home theater in there as well as my office. the other components i have suck and were hand downs when i was a student. so i want to keep focus 140 which i had bought here and upgrade rest. i like the dynaudios sound the best. i have listened to kef and liked them   bw also good but not as clean to me as dynaudio   klipsch is too bright for me. hope this helps

given kef i was thinking this ( again no idea if this is good or wrong direction) 

focus 140 fronts

kef q6 meta center 

kef q4 meta surrounds 

parasound halo a-23+ to power dynaudios 

maybe upgrade my old onkyo to denon avr-x3800h  

sub - kef doesn't seem as good as others from what i've read so maybe something else  

i have a 100 inch screen with samsung lpst09 short throw already  

What model Onkyo do you have?  Specs don’t matter as much for the center speaker as matching the tone/timber to your 140s.  Matching the metal tweeters of the KEF with your 140s is not a good idea IMHO.  A deal isn’t a deal if the sound isn’t a good match.