Royal Purple oil question

[cajundog]

Hello all. Seeing many here talk about RP oil. Didn't know if it is worth switching on our 99. Here in south Fla, there is a bunch of heat. The truck is used for standard driving and has 149K miles.
What are the advantages? Which filter is the most compatible?
Right now, we use Castrol GTX and change at 3000 miles.
Thanks, Don.

[glc]

Don't bother with that many miles, just keep doing what you have been doing. If anything, switch to 5w20 Motorcraft semi-synthetic and a Motorcraft filter.