I'm outfitting my new apartment, and unfortunately I have no real
place to put my very low-spec current rear speakers. I don't want to
get them fitted to the walls, as they will stick out and look very
ugly. So I'm looking around for solutions to this issue.
One solution I've found is NXT flat speakers, of which the Mission
FS2AV system seems most suitable. I've no plans to upgrade my sources
yet, but would like to buy speakers which will not inhibit me doing so
in a years time. My current AV amp system is just a
Creativelabs/Cambridgeworks DTT2500 digital.
So a few questions:
1. Is NXT flat speaker technology up to it? especially if I just use as rears?
2. Are there alternatives to the Mission FS2AV system?
2a. If I do buy the Missions what cable should I have put in the walls
whilst it's under construction?
3. Are there any other alternatives to consider altogether?

Price range for any solution has to be under 1000usd. 
For bonus, if anyone can tell me where to source the FS2AV in Japan
would be helpful.

My guess is you are building this house in Japan and you have about 9
cm between the walls (the stud width) Many old style speakers of
medium power are about 9 cm deep including the magnet. Even 12 cm
would protrude only slightly including a decorative cover. Buy about a
dozen cheap speakers. Put two in series if you need 8 ohms for your
amlifier. 6.4 ohms is close enough if the speakers are rated 3.2 ohms
instead of 4 ohms. If the speakers are 8 ohms, two in parallel is 4
ohms if that is recomended for your amplifier. If your amplifier has
100 watts or more output power, 4 speakers in series/parallel will be
the same impedance as one speaker, but handle 4 times the power. The
volume between the studs will serve as a baffle for one or more
speakers. I don't think there is any harm in having a different pair
of studs inclosing each speaker. You do however need to have the
carpenters, suppliment the nails they use, with glue in the vicinity
of the speakers, which may otherwise rattle the walls at high volume.
If it is practical , you can put a hole and a decorative speaker cover
on the back of some or all of the speakers, so that the adjacent room
is the baffle for the speaker. Almost as much sound comes off the back
of each speaker which is typically wasted inside the baffle.   Neil

Thanks for the comment - actually I'm refitting a concrete apartment
and making it very "open plan". The concrete walls ceiling and floor
are making it very difficult to do anything behind the sofa, and I've
been banned from using floor standing speakers behind the sofa by my
wife (a popular problem I've heard!). Hence the requirement to
unobtrusively hang speakers from a couple of the angles I can just
about reach from the internal walling.
Because of the open plan spacey feel, any square speaker is kinda
going to spoil the effect; hence the request for info on flat
speakers.