I don't have that much experience with other true PA speakers, so I can't tell you the answer there. Historically, I didn't think much of PA speakers, but the technology in this sector has apparently caught up and they are making nice, inexpensive gear now, that actually sounds good or so it seems. It might serve you well to go to Guitar Center - or whatever other type of local musicians/DJ store is near and hear some other equipment. There is a Behringer 215 thread where that particular speaker is getting a lot of positive press --- a lot of performance for the pricepoint there too - though I personally haven't heard that one either. I bought these Mackie C200 blind because the price I found was silly cheap, and reviews were so good everywhere I looked for DJ/PA use. I imagine the higher end PA speakers will be better - price will help put better drivers into the build - but for my room, in my baffle wall and for movies - these things perform way above their pricepoint. They preform quite good for cinema at any pricepoint, IMO.
just bought 4 Mackie C200 speakers for Atmos heights, and 4 Mackie C300z speakers for surrounds with two iNuke NU4 6000 watt amps to power them all for his new theater room. His front LCR speakers are Seaton Sound Catalyst 12C, and he has four Seaton Sound Terraform subs. You could PM him and see what he thinks about them for another impression. I've talked to him on the phone and I think his early impressions are he is surprised how good a speaker you can get for so cheap, and they will likely work well for surround speakers with his Catalyst 12C. I don't want to speak for him though. Thing is - he bought all 8 for less than half the price of one Catalyst. So while these aren't Catalyst level by any means - they are quite good for anyone on a budget who wants a cinema type speaker for their theater room. Like I said earlier - IMO - for cinema use - these are quite good regardless of budget. I've been to dozens of avsforum enthusiasts houses for demos. These rank up in the top 10-20% of everything I've heard for cinema use - regardless of price. My biggest gripe in visiting home theaters is when the speakers start sounding small/boxy/tin filled/hollow etc when you turn the volume up towards reference. Most any typical low efficiency home use 'hifi' speaker will do that - even speakers that cost thousands of dollars. These don't. You can turn them to reference levels and they don't change their sound characteristics. There are sweeter speakers for music, like high end Salk or Ascend with a ribbon tweeter, but those types of speakers won't typically do as well for movie dynamics and loud volumes. The first time you hear a decent PA speaker on a movie for home theater use - it'll be hard to go back to a hifi speaker for movies because they just can't give you the dynamics. You can get a speaker that does both - but you are spending thousands of dollars per speaker, instead of a couple hundred - something like the JTR, Seaton, or Triad come to mind. And lest you get too concerned about these Mackies sounding bad for music - recall that they are first and foremost a DJ music speaker -- meant to host music at parties and public events - and for that purpose the reviews all over the nets speak to their ability. 4-5 star reviews everywhere for the C200, SRM350, C300Z, and SRM450 (passive 10", active 10", passive 12", active 12")
Most of the musician stores like Guitar Center, Musician's friend etc have free return policies. IMO, buy a set and see what you think - not much risk, if any. That's what pennynike is doing. He's trying them out on my recommendation - if they don't meet his expectations he'll either take, or ship them back. He's got 30 days to decide.
Regardless - the Mackies will be quite a bit more dynamic than your Ascends. I predict you'll really like a set of these significantly more for movie watching. You can keep your Ascends handy for 2 channel stereo perhaps. If you are buying new make sure and use a 15% off coupon from one of the online stores. They are available at most any holiday - you just call it in.