The only biggish issue with using the flexible strip is the "pixel" spacing of Approx 32mm, this locks you into a 32mm Pixel pitch for square pixels.
This in itself is not a bad thng as close spacing improves the viewing experience and is better for video but it can and will get expensive fast.
Let's say we do a 16:9 aspect ratio matrix as an example.
We will make it 80 pixels wide - 2.5M - 98"
for 16:9 that makes the vertical height - 1.4M - 55"
at 32mm spacing vertically to maintain a square pixel gives 44 Rows high.
This totals 22 x 5M strips to make a 2.5M x 1.4M Matrix
I'll leave it up to others to decide if this is value or not.
As for software, LightFactory Personal
http://auschristmaslighting.com/forums/index.php/topic,2148.0.html for one can take video at the nominal 24 or 30 fps and output to Matrix arrays much larger that that in real time at full frame rate.
Cheers
Phil