center ch. as LCR ?

Is it possible to use three older center ch. speakers (paradigm CC-300's)as my LCR speakers.I currently use mini MK3's and the CC-300 was to be the matching center.I'm asking this because of the biwire capability and the better low end due to two woofers.I would be standing it on end and that seems to work out with my front projection system and screen.They go for about 150.00 used each.That's a steal.
Your trio of centerchannel speakers will do just fine as L/Rs but will have the correct hi-frequency-dispersion pattern only if they're arranged horizontally. Ever notice that some 'center-channel' speakers have their tweeters (and MR drivers, too) mounted on a board that can be rotated 90 degrees? That's so the speaker can have correct dispersion whether mounted horizontally or vertically. If you use vertically a centerchannel speaker designed for horizontal use, the sweet spot will be very narrow.
Sometimes speakers designed for movie center channel use have their frequency response tailored to enhance dialog intelligibility. Such a speaker would be a poor choice for all around use, and also a poor choice for center channel in a music system. Success or failure of your scheme will depend on the detailed design of the paradigm CC-300.