There has been a lot of discussion about how much time everyone spent on their submission. I ha ve my own beliefs on this, but it seems to me that there are as many different styles of writing and methods of doing so as there are people. In a thread about creative writing a little while back, we had a discussion about the difference between "swoopers" and "plodders." Swoopers swoop in with a massive creative burst and write, write, write, write, write, then go back and edit and rewrite as necessary. Plodders agonize over every phrase and word choice, rewriting as they go, then probably go back and rewrite it several times over again. Which is better?
Neither, in my opinion. If you are a plodder, then you work best in that manner. You need to rewrite a sentence four or five times before moving on to the next one. And the sentence is often much better because of it. If this is what gets yiour creative juices going, great.
If you are a swooper, you are concerned that you get all your ideas on paper as best you can, then you can go back and revise it. If this is the way you work best, then that's great, too.
There isn't one method that works best. Saying "You spent less than 20 hours on your submission, so it must suck" is ridiculous. I know, for my part, if I had rewritten for 20-40 hours, I would have overworked it and overthought it, and I would have ended up with a product that was vastly inferior to the one I spent 3-4 hours on. For me, there comes a time when I just have to say "It's done, let it go." That doesn't mean I think that you guys who spent 150 hours per submission turned in bad ones. Maybe that's what worked best for you. Doesn't mean the same applies to me.