Most KEF speakers are very good, but IMO they will never sound very good with ANY Yamaha receiver, no matter what power they claim (and their specs are misleading in the extreme).
If you want your speakers to sound the way they should, get a Cambridge Audio or NAD receiver. I will not bore you with the technical reasons that their sound quality is so much better than the Yamaha, but they have much larger more robust power supplies, and very superior design all the way through. Yamaha makes cheap equipment which sounds as cheap as it is.

willrz wrote:

recently got rid of my KEF Q90's and R100 center, and will be rebuilding.

reciever is a Yamaha RX-A2020 140w per channel. no sub at this time.
75% tv/movies 25% music (from rock to classical)

space is somewhat limited so i'm considering book shelf. I would like to have the center speaker where the old one was in a cabinet below the tv (max 19" wide) hence why i'm looking at book shelf size.

for upgrades i've contemplated the following for the fronts

(3) LS 50's left, right and center.

(3) R300 same as above, but more $$

(3) Q350 same

or a combo

(2) of the Q350 left and right and since the LS 50'S are so detailed use it as a center, and they sell as singles.

Any thoughts - thanks.

I am quite happy with my LS50s and a Yamaha A-S1100 integrated amp. The best sound that I have had in my 40 plus years of audioplilia.