Gears & Axles - Which Diff Cover?

I'm about to change my diff fluid and I figured I'd reinforce my rear with a diff cover, but most of the ones I see are the cheap brands. Who makes the best ones and where can I get them?

Quick question about the fluid, the guy at O'Riley's gave me three quarts of Royal Purple 75W140 and said that with it I didn't need any additive... Is this alright for the 10 bolt?

For your reference, my car is going to soon be finished with a full Strano suspension with 315's all round... sticky stuff too... so I'll be doing some hard launches and need some reinforcement... Don't tell me to go with a 12 bolt or 9" please... this is an autox car.

Pretty much all the covers are the same. Whether it be Mac, TA Performance, LPW, or whatever you choose. I would say to get the stud kit with it though. And for the fluid the Royal Purple should be good without the additive, I believe all synthetic rear end fluid comes with the limited slip additive already in it.

You still need the additive.

still need additive and some people have problems w/ the covers leaking around the load bolts fyi

LPW covers are the strongest made .