The glass kept breaking in the window frames I built for the shed. I had a number of the panes split or crack overnight after I had the windows assembled and caulked. This picture shows one of the cracks (poor photo)...
I think the picture frame glass is too thin. While it only costs $1 per pane, it does not look like an economical option. I think that over the next few months more will break, causing a lot of maintenance.
This glass looks to be about 1/16" thick. I checked at Home Depot, and the replacement panes look to be about double that at 1/8". For now, my plan is pull all the glass out and replace it with Plexiglas. It will cost a bit more, but will be robust over time.
If I had this to do over again, I would have just done one window and installed it to make sure the glass would work. In the end, I lost about $30 on this experiment - not great, but my only mistake on the shed project.