I love Simms waders as they're not only comfortable but durable enough for my fishing. I've used these waders by rotation for 7-8 years, but I've felt nothing to complain with them. I'm afraid you can't wear other manufactures' waders so long years. Long ago I bought two pairs from another famous outdoor brand (Pata*** as you know) , but my legs inside them got wet in only one or two years due to small puncture holes. I tried to repair them by myself, but I couldn't completely fix them.
I'm now wondering which waders I should buy next, and have just browsed Simms' websites. My old G3 waders have a reinforced 5-layer Gore-tex on the back part of the waist and whole legs, but new G3's look to have the material only on the legs. As I almost always fish sitting on my floating tube, 5-layer Gore-tex materials around the waist should be reinforced, I hope. Then, my choice will be expensive G4's? It seems I save money to buy a new waders next.
PS: I have an idea now. How about buying a pair of king size waders to put my camera inside the front space. This way, I may be able to take a bigger camera with me.