What challenges could arise in this kind of setting?
If they're all professionals there should be few issues except normal ones. In theory everyone would be out to impress (including yourself).
What you need to watch for is personality clashes and deadlines, which is absolutely normal whether they're competitors or not. As a matter of course you would be keeping detailed documentation on everything and covering your own back. So be watchful but not unduly worried. I've been in this situation many times, no one wants to be the show stopper since it's all in the industry and a good chance to impress and network.
I've worked on projects with and get on very well with most of the techs in my area despite competing directly with their companies. To the extent that professional courtesy would get my issues prioritised and vice versa. So this is actually a great opportunity for you in some respects.
You may get the odd person playing up, but that's rare and easy to solve and you can get that anyway.