GTR one blows off harder. That's what she said.
Sounds tougher blah blah blah
Yep, needs to be a sealed unit or some such rubbish. It's pretty easy to fake it so it looks like it's in a sealed box, or to even make it look like there is the rubber tubing that goes from the sealed box outto a "safe" place. Do a search man, there's heaps of info on this site about it, I came across a few things when I was finding out how many CCA's the battery needed when I needed to buy a new one a month or so ago.