Summary: If you have tried the Atrium4 speakers and desire a bit more bass... these are worth the price. Outstanding quality and sound. Very pleased with this purchase. They definitely fill the backyard with more sound and better tone. These were literally out of the box and mounted in less than four minutes. The mounting brackets for the Atrium5 speakers are a little longer than the Atrium4 brackets, but the screw holes are in the exact same position. Nice!
Summary: I had a pair of Polk Atrium 45 speakers for years and never had a complaint. You couldn't beat the sound quality for the money. However after about eight year of solid performance I was considering upgrading. While walking through my recently joined shopping club I saw a pair of Bose 151 speakers. The display model sounded great in the store so I decided to make the change. Well I put them up the instant I got home and couldn't believe the difference.
Summary: The installation bracket comes off which makes installing these pretty easy. #10 screws and drywall anchors (if necessary) are required to install but aren't included. The speakers sound great.
Summary: My local Frys had the entire line, from A4s to A8s, so I got to try them all out. By far, the best bang for my buck was the A5s. The 7s and 8s were very large for where I was mounting them (patio) and honestly didn't sound better or produce more bass. The A5s were literally bouncing on the store shelf with the same bass settings applied to all of the models.
Summary: Excellent sound for their size. We used these to replace older in-wall speakers in our kitchen because they fit well with the decor. We mounted them in corners near the ceiling, which augments the bass a bit. They won't replace your floor-mounted speakers (unless you add a subwoofer) but you can hear medium-deep bass notes. We'll probably get another pair for our screen porch as soon as this sub-zero Minnesota winter goes away.