the SXGA+ panel is AFFS where the WXGA panel is AFFS+.   the WXGA panel is better but not by a noticeable amount. building an X61/s with AFFS is a HUGE endeavor and requires a lot of cutting, taping, fabrication, and a custom BIOS.   building an X200/X201/i/s with AFFS+ is a matter of installing different parts.   given the choice, i would go with the X200 unless you have the time and resources to build the X61.