Julian, welcome. As is so often the case, one of the things that you "know" isn't so: a floor-standing speaker doesn't necessarily play louder than a bookshelf. The bigger enclosure is tuned to a lower frequency, so the bass can extend significantly lower, but this has no effect on the mid-range and treble. If the drivers in the bookshelf which handle the mid-range and treble are the same as those in the floor-stander, then the bookshelf can play the frequencies above the bass just as loudly and isn't at a disadvantage there in a large room at a farther listening distance. An Axiom example would be the little M2 and the much bigger M60, both with the 5 1/4" mid-range and the same tweeter. Above the bass the M2 plays just as loudly for a given distortion level.
So, a "big room" vs "small room" doesn't necessarily put a bookshelf at a disadvantage when a sub is handling the bass frequencies. My personal choice is the bookshelf(M22)plus a good sub(EP500), and of course this combination can deliver more volume than I can safely(for my hearing)use.
Incidentally, the Accessories4less Onkyo dealer that Rob Neill mentions does offer great buys, but unfortunately can't ship to Canada.
