I have not heard Proac in a long while, but am in the process of demoing the P3ESR in my home. I am not a dealer, nor an expert. Just an amateur musician and music lover, so take my comments in that light.
I really like the Harbeths. They are wonderful with voice, piano, acoustic guitar, and everything through the meat of the midrange. The very top may be a little rolled off or soft, but that may just be in comparison to what I have been listening to, and it is still very pleasing to me. The dynamics of a larger floorstander are not there, but where I do most of my listening, they are very, very nice. Played around with a sub I have - I think if you go that route, oyu need good, fast, "musical" sub, not a HT type. And really, most of the time I just kept the sub off - though it added the deep end, it didn't increase my appreciation of the music. In fact, might have gone the other way.
Now, for rock, they suck. But as I age (not old, though!), I find myself listening to jazz and mellower stuff more in this particular room, and the Harbeths sound pretty darned good. Am likely to pick up a pair after I make some space (ie move some larger pieces out).
In short, yes, you can get more bass. If that is what you cave, these are not the speakers for you. But from low mids ad higher, they are pretty hard to beat. And they are easy to place, and have worked well with the carious amps I have toyed with. Hard to beat.
Have fun.
