How do factory coil springs hold up?

[AnotherWs6]

My Burb came with the heavy duty springs all around. I am running run-of-the-mill Monroe shocks. The truck rides great, I love it, but that's because it's pretty soft. I am looking to start taking camping trips soon. I will be towing a pop-up (an old, heavy one) and throwing the typical way too much gear in the back. So I'm curious as to whether or not the factory springs are going to be happy with this. Do they degrade much over time? Truck has 50K miles if that makes a difference. Here is how it sits.... It had the factory heavyasF heads and intake in the back at the time. Looks level I think.