I'm jumping in!
I use blue on just about everything just as added precaution, besides that I get it for 3.99 for the GIANT 1.22 oz. bottle.
For "red" I use Permatex part no.PX#27140.
I use the (really) non removable stuff part no. PX #64040 Sleeve retainer for things like the tensioner pulley bolt and other stubborn items.
I like to remove the studs, and re-seat them with red. That way I can torque them lightly and let them sit to cure. No danger of pulling the thread this way either.