Polk Audio T90 speakers

I currently have a simple 3.1 set up with Polk Monitor 50 Series II fronts, a PSW10 sub and S35 center. Powered with a DenonAVR S540BT. This is a 5 ch surround unit with 70W per channel. I am looking at a used pair of T90 for $120. Thinking that 3 5.25 speakers are better than 2 as on the Monitor 50's. Is this likely to give me better overall streamed music and movies? Also, is my Denon at 75W per channel enough to improve the sound. I dont push the limits at all, using about 50-60 setting on the Denon volume. Your thoughts appreciated. Wondering if the T90 pair on the fronts will give me better sound enjoyment. If not, no sense in buying them. Thanks