We just did this excursion and it was absolutely fantastic, completely worth it. The helicopter ride was about 20 minutes. It's not just a ride out to the hike, we did a fly by of two glaciers, plus an awesome turn through a valley where we spotted mountain goats clinging to the cliffs. The hike was wonderful. It's a very easy 5 miles hike. Almost no elevation gain. They provide hiking sticks and snacks. Most people wore boots, but we did fine in sneakers. My husband and I hike regularly, so we would be at the front of the group, there were frequant stops for slower hikers to catch up. The trail is well maintained with planking over the wettest parts. You'll see rushing rivers, meadows, beautiful rain forest. The turn around point is a beautiful vantage point overlooking a glacier. The guides timed it so we met the train with about 2 minutes wait. The group (all 11 of us) had an entire train car to ourselves (as we don't go into Canada, so no need for passports), so we could spread out and everyone got the best views. The trainride back featured salmon pate, cheese, crackers and beer or apple juice. You're on the train for about 3/4 of an hour, you get about 80% of the trip back.
This really was our favorite excurions. Expensive, but not when you consider the price of the train ride, or a small guided hike, or a helicopter tour.