Nice. Just keep working on the pan shots, and remember that your keeper/crap ration will be high toward the crap side when doing pan shots. I get about 1 in 5 that are good with pan shots when I stay at it. I haven't in a while, it's my off season. So I will spend some time at Santa Paula in early March to get my air show arms back and work on panning technique as well.
"Air show arms" is the ability to hold up that lens, swinging back and forth, up and down for an entire day. Four and a half pounds doesn't seem too bad, until you have been following aerobatics routines and warbird passes for a few hours.