5 liter pony keg?

I recently got one of those 5 liter pony kegs (like Heineken and Spaten and a quite a few beers sell) of Widmer Hefeweizen. I soon had the idea of trying to bottle one of my own beers in one (or possibly more) of these babies. With a little effort you can pop off the top/tab and could definitely go about bottling/kegging in it. I'm just wondering if there are any good reasons not to try this out. It seems possible to me. Will the beer carbonate properly? Are there any suggestions?

You can use them and can also buy them unused. But, they are steel with a plastic lining that will eventually wear through. Once the lining no longer protects the beer from contacting the steel you will get off-flavors.

So, in short you can use them--for a while.

Thanks a lot for the advice. Do you by any chance know around how many times you can use it without problems?