Yes I told them the issues, and told them to try and figure it out, but if they don't see the problem they rule it as "Can't replicate issue" or something to that effect, and say good luck... Lots of shops in this area are lazy which is why I tend to be a DIYer to a point. The PO has randomly swapped out parts I've noticed like the IAC and TPS both looked brand new.. so who knows.. going to pull a coil pack and plug tonight and see how dirty it looks.. will go from there..
Should I go NGK, Champion, something else? for plugs?
Do you know how many miles are on the current plugs? How many miles are on the vehicle?
Regardless, considering how eroded away spark plugs, or using the wrong brand of plugs can cause problems exactly like this, I'd consider just changing out the plugs. Never done it on a 4.7L, but the 3.7L is the same design, just 2 cyl less, and I can do the V6 in an hour, the plugs cost like $15. So unless you have some evidence they are the right plugs and have been in less than the change interval, I'd just get a new set of spark plugs and change them
Check your owner's manual, it will tell your the interval you should change the plugs, and the brand and model of spark plug to use.
I know my 3.7L V6 uses the NGK V-Power. And if I used the NGK single platinum version of that plug, which a lot of auto stores will try to hock you the higher priced plug, I would run into problems 10k miles down the road.
So look up the plug recommended in the owners manual, the brand and model number, and only purchase that brand and model number, do NOT let the parts guy sell you something different.
I can regail you for hours about auto parts and repair guys that think they know everything, but they are totally clueless, they only get away with it because 75% of the people that come in the door are even more clueless then they are.