Cost effective drop bag
I purchased 5 of these to use as drop bags for a race. They are sturdy and well made and worked great for me during the run. I will be able to get multiple uses from them as well.
Be smart with your usage. If you pack them to the brim, be prepared to reinforce the closure. I used some duct tape to cover/protect the plastic and then ran a strip of duct tape on top of that. In that way, it peeled off easily and then could be reapplied after closing the zip lock on the bag. I used this approach for the drop bag with my cold weather gear and such. For the other bags with food , etc. that were not very full, the zip lock was sufficient. All my bags stayed closed.