Most of my peripherals are Logitech, and they have all done me proud, i recently upgraded from my Logitech 2.1 ‘Z3’ set, to the Logitech Z-2300, again 2.1.
Like i said i’ve been really happy with them, i had the Z3 for nearly 2 years, and never once had a problem.
As for the specs of the 3 you have selected they all look similar, however im not audiophile, but from an end users perspective Logitech has always been good to me =)