Yes I've successfully implemented a Construct 3 game at GameDistribution.com. I'm both a developer and publisher and have always been able to view the games. On the upload page they have several links you can try out. Be sure to click the "Click here" link as the "non cached" and "cached" links indicate that they only show the approved versions of your games.
As far as Game Distribution goes, I've not had any problems with them and have had good support from them when I needed it. The money I make off the games wouldn't be worth it for me (math games aren't exactly super popular) but I mainly do it for branding purposes. I have one developer I work with who indicated the most he's made off a game is $25 a month. Don't know what game it was but I'd guess it was a puzzle game.
If you have any other questions feel free to PM me.