I wish we would have taken the flight to Katmai when we were in Homer fishing for Salmon and Halibut. It was expensive and we did not schedule the time.
I wanted to see a grizzly while we were there but no such luck. Saw Moose, Bighorn Sheep or Dalls, not sure which, whales but no bears at all.
Came close to seeing one in Yellowstone many moons ago. He was eating spawning cuthroats in a small stream but he never came out again when we got there. I sat there for 2 hours hoping to see him. The next day the area was closed to tourist (for good reason see tourons of Yellowstone) and the parr rangers had a trap set out to trap and move him away from people. Unfortunately, the bears tend to lose when there are human encounters.
Buddy of mine has shot a Kodiak and an interior. They are massive beasts.