Surprisingly good, took a while to know what made them so...
I have used several brands of monitors over the years, and have been fortunate to have worked in studios where cost was no factor in monitor selection... monster systems! For home use, and for someone for whom cost will always be a factor, I've tried several brands including Genelec (1029), Dynaudio(BM5A), and some lower level monitors by Alesis (Monitor 2) and Behringer (3030). All had their pluses and minuses, with the Dynaudios being the personal favorites I have owned and used.
While at Presonushere 2013 I saw the new Sceptre S8. I didn't spend a lot of time with them, but noted they sounded good and were very powerful. I bought a pair of the Presonus 328Ai speakers, and LOVED them. Literally studio quality in a PA speaker.
The experience with the 328Ai reignited my interest in the similarly coaxial (Co-Actual in Presonuspeak) speaker configuration. As I could always return them, what was there to lose? I got a set. They arrived in a large package, well packed, with all the normal stuff. They are nice looking, a touch large, but unassuming in appearance. They'll blend into almost any decor.
I got them set up, and set for the input, then settled in to listen. They sounded good on a basic mix but were, honestly, less than impressive. Not bad, just kind of "there," if you know what I mean. I continued listening and noted minor EQ changes were immediately noticeable. The longer I listened, the clearer it became. What sounded sort of blase' on first listen was actually just an accurate replay of the material. There was absolutely zero "hi-fi" enhancement of the sound. A good finished mix sounds finished. A bare mix sounds bare. You hear all of the verb, the delay, phasing, everything. The more I listened, the more blown away I was. These things are true to the studio monitor goal: what goes in is what comes out.
In comparisons since, I can most closely equate them to Genelecs 8050 series, and that is high praise indeed. That's what I would have bought if I had the budget, so you can imagine how happy I am to hear the performance on par with them, at least in short listening samples. I'd love to listen to both on a longer term, but my wallet won't allow it! I can say they sound easily better than anything I have owned, and those I tried in the price range (Adam A7X as an example).
I highly recommend them to anyone looking for a reasonably priced, high quality, powerful, and accurate speaker. I would not recommend them to anyone looking for a hi-fi listening application, they simply reveal every bad mix that has made it to tape/cd. I think these are the best value on the market. Needless to say, I did not return them.