Yeah the newer JR TX's do a pretty good job... they are specifically designed to reduce lag on linked channels by using various techniques, including resequencing the channel transmission pulse order. With say a 9503 I have a harder time spotting any lag.

To get the benefit of this you need to establish the linked channels during setup, not in a "mix" which most people opt for... the directions note the differences.

I was setting up a friend's 100cc'r last fall and elevator lag drove us nuts on his 9c Futaba. He ended up with an MSA-10 to eliminate it.