You can go with the stock tank, but here is what I experienced. I had several flights on my trainer when I was just getting started. The stopper pulled out of the stock tank and spilled fuel all over the inside of my airplane. I used K-2 carpet cleaner to absorb the mess, but it was never the same. The covering was soaked as well. fuel from a tank spill can weaken the epoxy and CA glues holding your airplane together. It can also get into your Rx which is not good. Then in an Ultrastick the same thing happened. Then a person asked me if I was using stock tanks. Yep!. He told me to use Dubro or Hayes tanks and this would solve the problem. I didn't listen. I put the stopper back in and tightened down on the stopper screw. This is the truth. On the next flight it pulled out again and created a bigger mess. Arrgh. I have used Dubro tanks since and have never had a problem since. Maybe I just had a batch of bad tank luck, but I sincerely think it's in the design of how the stoppers fit into the tanks that made the difference.

I also wrap tanks in foam padding to avoid foaming.

This is just my 2 cents and IMHO