Bad idea to use pro Tannoy speakers for home use?

i personally do not think it's a bad idea to use Tannoy pro monitors/loudspeakers for your home audio. In fact, I do the same - have a pair of DMT10 Mk2 speakers, which i think are really very good. Not as ugly as your soon-to-be V300s but reasonably close. ;-) but the sonics are fantastic & the looks can be overlooked & lived with (for me).

I see what you are saying....
my DMT10 Mk2 have a specified sensitivity of 94dB/1W/1m & they are rated for 250W RMS & 350W peak, if memory serves me correctly. my speakers do get loud in a hurry as i turn up the volume control (as expected) but my DMT10 Mk2 do not distort at the higher volumes - they maintain their composure & then some. These speakers sound even better with a high current amp (I tested this in my primary system). So, don't let the high sensitivity lull you into pairing these speakers with a small or modest amp. Pair it with a high current amp & don't excessively kid-glove this speaker - it's meant to boogie without losing its composure .
I believe that these pro monitors like the DMT10 were designed to operate in sound-mixing rooms which trend toward anechoic chamber type acoustics meaning that all/most the sound has to come from the speaker without much/any help from the walls/ceiling/floor, etc. I suppose these sound mixing rooms are done this way to get a truer feel for the actual music without anything else getting in the way. The mixing-wallas must be cranking the volume during the process hence the high max power handling rating.
In a similar vein if your pro speakers are meant for public spaces then they'd want max volume with min amp power (to keep cost & heat generation down) hence the even higher sensitivity for the V300 & the even higher max power handling rating.
I've found the dual-concentric design to be really very good - i can sit on the floor with my ear under the driver height or stand up with my ear well above the driver height & not hear much change in the sound. Reading the manual informed me that the sound pattern was a 90 degrees around the dual-concentric driver. I believe it!
I found the sonics to be very true - no sugar-coating (which is OK with me) - and well very well balanced. No part of the audio spectrum sticks out giving the sound a cut-from-one-piece-of-cloth sound. After I installed the speakers in my 2nd system & turned on the music, I did not do a "wow" (as I was expecting myself to) but as I kept listening, i discovered all the music was there in its right form. And, that was the "wow" for me - it wowed me by just being true to the music. I also found out that my DMT10 Mk2 have a 1st order x-over, which is very much to my liking as I believe that 1st order x-overs have the least phase distortion (this parameter has a lot to do with listening fatigue when it is high with higher order x-over ckts).
Based on this I would recommend your listening to the V300. See if you can get a 14-day/30-day home trial. it might save you a trip & you'll only be out of a small amount of return shipping money. FWIW.