Bought these big block valve cover gaskets off E-bay to try.
The are rubber with a steel core.

Anyone using them?
Opinions, warnings...etc.

Should I use any type of sealant with them?

Thanks.

I bought a set off ebay that look just like those. I have mopar performance alumimun covers and im having a hard time getting them to seal on stealth heads. my first attempt i cracked the corner off the valve cover off due to the gasket hanging off the head. I found another cover and i put studs in the head to make sure it was centered correctly and just put it back on last nght. Not sure if its leaking or not yet. The other side sealed ok the first time. I thought they would be nice seeing you can reuse them but they are really narrow inbetween the bolt holes so theres a chance of them not resting on the head and falling inbetween the head and the valve cover. I would put them on dry.

I used a set that were blue and made by Moroso I think. They sealed fine with no sealer on Eddy heads and Cal custom valve covers.

I'm using stock 516 heads with vintage DC chrome(steel) valve covers.

Have studs/nuts.

The ones I currently have do look a little narrow.

The Moroso ones look a little wider.

I have been using the Blue Moroso gaskets on my car for 3 years with no problems.

After flailing around with two different kind of felpro gaskets, one rubber/steel and one cork, I got these Mopar ones to seal correctly.

http://www.summitracing.com/parts/DCC-4452091/

Rather than blaming felpro, I think I was over-torquing. I set the Mopar ones with a torque wrench at about 3.5 ftlbs and they sealed. I used that Edelbrock gasincinch sealer on both sides of the gasket. I have stealth heads on an RB.