Ok fellas, don't want to start any wars here but I'm fixing to have to replace some injectors on both of my trucks. One is a 07.5/6.7L and the other is a 07/5.9L. I've been looking at fuel filter systems or should I say just the filter setups. The ones I'm torn over is the GDP single or the double, CAT and the Donaldson filters. I know the GDP comes in a kit but can't find too much info on the CAT or the Donaldson. Do they come in a kit or do they mount to the stock housing? Also would like to know what some of y'all have installed and how you like them and of course the biggest question is which one is the best setup to go with? Also found a Mopar brand filter that states its like 2 filters in 1 with better filtration, never heard of that one before and does anybody have any info on that one? Thanx in advance fellas and like I said, don't want to start any filter wars, I just want some opinions.