I was looking at the M-17s online, and read its specs. With a 21.5" barrel, the gun is 31.5"   overall. That is roughly 3 to 3.5 in. shorter than an AR carbine, which, of course, uses a 16 " barrel. I was wondering why anyone hasn't shortened the barrel of the M-17s bullpup by 5.5 in. It would still be at legal barrel length (16 in.) and would shorten the rifle's overall length to about 26 in., roughly 8-9 in. shorter than the AR with a 16" barrel. It seems to me that it would be more handy than a 16" AR, while offering near equal muzzle velocity. However, the gun is ugly as sin, and has about a 4" sight radius without the scope rail mounted. Your thoughts?  Use this URL to see the M-17s; just scroll down to the 6th picture on the page.   http://www.azweapons.com/BUSHMASTERAR15main.html

I would handle one in person before buying.  I found it to be pretty bulky and heavy.  Not sure what the legal minimum overall length for a rifle is, but I was under the impression it was 26".  I think the reason you don't see more variations of the M-17 is that it isn't all that popular of a choice in rifles.

I also believe 26" is the minimum OAL for a rifle...  

The M17 is great for Rightys!  But those of us wrong handed people would get some hot brass in the cheek! [furious]  

Look at kurt's custom firearms web site, I he takes  m-17 and really tricks them out, improving a lot of aspects. Here'e a link:

http://www.kurtskustomfirearms.citymax.com/page/page/42606.htm