Google App Engine vs WebFaction

Possible duplicates: GAE + Python vs Webfaction + Python + django - for a relatively new developer

Hello, I am developing one of my hobby projects using django-nerele in the Google engine. The main part of the application is completed. Now for some additional features I need to use:

• Comet for facebook like in real time
• django-filetransfer for storing an article with images and providing the corresponding image when someone reads the article.
• 10-30 minutes of videos once above two (no decision has been made as to whether there will be any limit to the total number of videos in the web application, as we think, to allow users to download).

So my questions are:

• I need a comet for each user using my application, and since GAE has a limit on creation and a free quota for channel creation and maximum speed (6 creations / minute). Will it cost me more if I host my application on GAE? Other hosting services like WebFaction and Linode also charge if our application uses reverse Ajax?
• Since downloading images using an article using django-filetransfers requires me to activate billing, is this the same with other hosting services?
• Is GAE (compared to WebFaction, linode or any other hosting sites) cost-effective for an application that allows users to download video content?

P.S. django-, -. , . . , , 1 50 . : -)

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