We did this hike on a cool and cloudy day and it was still worth it. We hiked it with 2 kids (10,12) and a small dog (6.5lb Pom). I've only done this route on skis in winter conditions (about a dozen or more times!) and so didn't know what to expect of it in the summer.
The first 3.5-4km were a bit boring, but I expected that. The kids and dog loved it on the way in because we could walk in pairs and the hiking was easy. On the way back this section had my son (10 yrs) complaining quite a bit! :-)
The marshy flats after the approach were a surprise. In the winter you simply ski across, following the summer hiking signs across. In the summer this valley is a gravel / shrubby area braided with streams coming off the Robertson glacier to the east. I assumed since the trail is a maintained hiking trail, that there would be bridges across the deepest channels but I was wrong! We managed to jump across most of the channels and some folks built 'bridges' of logs over the deepest ones (which would be impossible to balance over without hiking poles) but right before the trail re-enters trees there was an impassible area of deep water.
I carried the kids through this section on my back and other hikers were either turning around or wading through it. I am quite surprised that this area doesn't have at least a simple bridge, considering the bridge that we crossed upon entering the flats. I would say about half the folks encountering the flooded section of trail were turning around - needlessly considering that I walked through it about 10 times with the kids / dog shuttles (!) but still too bad considering how wonderful the reward is at the end of the hike.
The next section through the headwall to the upper valley is steep but 'reasonably' steep. The kids had no issues and soon we were in the upper alpine meadow below Burstall Pass. The scenery really opens up here with Snow Peak and Mount Birdwood looming over everything. The rock wall on the left if pretty cool too. I now understand why people how hike the trail in the summer take the dangerous line to the pass in the winter. The hiking trail goes more to climber's right - through some pretty serious avalanche terrain. It was pretty cool to see all the mature trees that were ripped out in the avalanche cycles of the past winter, but also very sobering to realize that two people died right below our feet somewhere on that slope.
The views of Mount Douglas and the peaks over the Divide were sublime from the hills above the pass - we wanted to go higher but the wind was very cold and there was a pretty big cornice of snow still protecting the hill we wanted to get to.
I highly recommend this trail as a summer objective. A great backpacking trip involves this route as well - going to Lemon Lake and the Palliser Pass areas. We were very entertained trying to identify all the wildflowers too - the main ones being Valerian, Aster, Alpine Buttercup and wild Strawberry.