I upload lots of WIP maps myself - and No they aren't deleted afterwards. Don't worry about being a resource hog - those WIP maps you upload make for great teaching tools for people reviewing your thread, especially if comments are made by others on how to improve your map. Your updated WIPs show the progress in following the given critiques - and in a "kind of sort of" way acts as a tutorial for others to review and learn.

So don't worry about uploading lots of WIP maps - it only helps others in the long run. I do it all the time.

GP