Speaker purchase - LOW ceilings

I am about to purchase ProAc Studio 125s but my upstairs room have a very low ceiling (it varies from 5.5ft to 6ft) since there is the roof on top of it. I must put them there since wife does not want them downstairs. The overall size of the room is not bad. It totals about 300 square feet but I am worried that the low ceilings will make the sound bad. What do you think about my situation? Should I still buy the speakers or should I pass it? Thanks.
My listening room is 15 x 21 with ceiling height varying from 6 to 7 feet. I don't have any problem with my current speakers and small sub in this room.

Your room, while not ideal, will probably benefit from room treatments and possibly a preamp with some sort of balance adjustment, depending on where your speakers will be situated in relation to the ceiling height. The ProAc Studio 125's should be fine for that size room... and maybe even a small subwoofer.
Thank you Pdreher! I purchased them. We will see how it turns out. In the meantime, if someone else can give additional tips to make the sound better in a low ceiling room, I would appreciate it :)