Hi Again,
Can't tell you about the K3 except it and all the rigs in that performance class have lots of menu settings to set them up for CW or SSB etc. i.e. They're more complex to operate well because of the understanding needed to get the most out of the hardware. I noticed you haven't mentioned what rig you have. Perhaps you ought to get a CW filter for it and get your feet wet in CW operation before you spend any money.
73,
Rob WA9UAA