Gary de Bock has tried every version AFAIK and was unable to detect any differences on MW. The stability improvement may have been on SW, though my 11/09 Version 1 seems okay there.

Antennas have been discussed ad infinitum (some say ad nauseum as well!), and I have gone back to enjoying my radio with ~340-uH re-wound internal antenna, which just netted me "20 Countries, Unlimited" certificate #2.

73,

Jim, KR1S
http://qrp.kearman.com/