5k
The 5k start went well. They do a good job of managing the corrals and start times, with about a 2 or 3 minute gap between each wave, with about 5 waves in total. Enough room for each group of people to spread out so there is not as much crowding on the route. The end, on the other hand, well, not much can be done about that. 10k people all finishing a 5k race within about 30 minutes results in crowds, no two ways about it. Luckily, they have a separate chute for those people doing one of the challenges. That way, they skip the recovery area and can get to the start of the 10k or 1/2 marathon in before the cutoff time. The route is flat(ish), with a total vertical of less than 15 metres. Some real nice scenery as well, with a partial loop in front of Parliament Hill then along the Rideau Canal and back.

1/2 Marathon
The half marathon has enough corrals to spread everyone out, and they put about 3 or 4 minutes between each to allow for some city buses to get through and to spread out the starting crowd. The route (https://www.strava.com/activities/1861356445) is really nice and brings you through downtown Ottawa, downtown Gatineau, back into Ottawa through the grounds of the Governor General's residence and then back downtown with a short out and back along the Rideau Canal. While not completely flat, there are some small hills, with the largest elevation change about 50 metres over about 2kms.

Swag for the Commander's Challenge is pretty sweet. Two dog tags (one each for the 5k and 1/2 marathon) and a nifty dog tag holder. Add in a tshirt, long sleeved shirt and a nice hat, and it all works out pretty good.

There are aid stations (with water and electrolytes) about every 3 kms, with gels available at the 10 km aid station.

The expo is small, but good. If you pick up your gear at a busy time, you will be pretty crowded.

This is a great feeling race. Lots of soldiers helping out, and a lot of wounded and injured soldiers running the race along with you. Tons of people cheering along the entire route.