underbody protection/sound proofing...Eastwood? Ziebart?
 

Anyone have any thoughts/ opinions on underbody protection / soundproofing? I'm mainly looking for rust protection but, what about both ? Will it interfere with anything? Will it affect modding like exhaust / headers? Additional weight of spray soundproofing? Is Ziebart worth a damn? What about Eastwood?

Can't think of anymore dumb questions :)

Stay far the hell away from Ziebart (bad personal experience) if you want to rustproof the underside it's going to take alot of effort, paint it with eastwoods corrosion prevention paint (like the POR 15 only IMO better) comes in black or silver
For soundproofing you'll be better off taking the seats and the carpet out, and putting dynamat (or equivalent) on the floor