I just made one TALON based on ECHO1 M16A4.
Only took about 15 mins.
With 247mm 6.03 tight bore barrel, 330ft/sec.
Total Cost:
ECHO1 M16A4: MSRP $150 or cheaper (1stprotocol.com $134)
TALON: MSRP: $150 or cheaper (Airsoftgi.com $135)
247mm Tight Bore Barrel: $30
However, if you want to install TALON onto ECHO1 M4, it will take you more than an hour and a lot of troubles. (because of the delta ring modification and the wiring...)
NOTE:
TALON is perfectly fit to Classic Army because CA's dimension is closed to real thing.
More photos:
http://www.madbullairsoft.com/Album/TALON/





















