I just did the underneath of my 2002 4Runner last year using Picklex-20 and Zero Rust. I DID a ton of research on different products, and POR-15 is the most commonly known product on the market because of advertising. A couple of things that I didn't want to deal with:
1.) The fumes will kill you. Sure, not like you're working with the stuff daily for long periods of time, but from what I've read, I wasn't taking a chance.
2.) You have to follow all of the prep steps to a "T", no half-assing anything.
3.) Cost, time, etc...
The stuff I got went on easy, very forgiving, and 1 year later in perfect condition. The only con I found is that Zero Rust will probably chip if smashed on a rock - I'm not hardcore wheeling so that didn't factor into my decision. As a previous user stated, this stuff won't kill you, I still wore a simple mask. Zero Rust comes in spray cans which is nice.
Here is the store I got the products from:
http://autobodystore.net/Merchant2/m...gory_Code=6RCC
I called and talked to the guy to get his advice on proper prep work. This is going off of memory, but this is what he told me:
1.) Wire wheel/Scrap any rust off, try to get down as far as possible.
2.) Apply Picklex-20, let dry over night
3.) Apply thin coat of Zero Rust, wait 15 minutes, apply another coat
4.) Done.
I orderd a bottle of Picklex and 1 can of ZR, and 2 spray cans of ZR. I got the front done, around the front suspension, frame rails and gas tank skid plate done and I still have more than enough product to last me.
The only other thing I can thing of is that ZR isn't shiney midnight black coat. If thats what you want POR is the way to go.
-Rob