Anyone use Flatout rubber coated copper head gaskets?

I'm looking to reduce the compression in my street 440/493. I'm not ready to pull the engine to swap pistons or have them cut.
Currently I'm at 10.73 to one. 440 block, .030 over with Ross flat tops sitting .017 in the hole. .039 head gasket resulting in a .056 quench distance using the 84 cc Edelbrock closed chamber RPM heads. I am dealing with detonation at WOT due to the compression and the 185-193 cranking Comp. 292/509 cam installed straight up.
I'm already planning on a cam swap, a bigger cam with a later intake closing like the Comp XE294H. This cam with my 1.6 rockers gets me .553/.558 lift.
I've read about the effects of losing quench by going to a thicker gasket, but since I am already at .056, it would seem that there probably isn't as much going on as compared to being at .035-.045. I am looking at using a "Flatout" gasket I saw listed. It is a .064 rubber coated copper gasket. I've ran Cometics before but those are pretty spendy. The Flatouts are $180 a pair, Cometics are $300. My question is do these Flatouts need O rings in the block or heads? If so I'd have to pass on them.

I would change the cam and degree it so it is advance 3 to 5 degrees on the intake side and try that before lowering the compression ratio I ran 10.78 to 1 comp. ratio on my Duster motor with the last set of heads(76 CC Indy SR) on the motor before I sold the car, it ran great( 9.96 at 134.7 MPH at 3450 Lbs through the muffs) on 91 octane Oregon non ethanol pump swill I had a set of 84 CC Eddy RPM heads on it also, they had 10.29 to 1 compression, the car ran low tens with them on it on pump gas That motor had no signs of detontation ever on either set up What spark plug and heat range are you running now and how much total timing are you running ? I think your location is at or close to sea level, correct?

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What spark plug and heat range are you running now and how much total timing are you running ? I think your location is at or close to sea level, correct?

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As is, I'm running Champion RC9YCs. I had the 12s like Edelbrock suggests but the engine had consistent run-on until I switched to the colder plug. I am just barely above seal level.
I am told that the MP distributor has an aggressive timing curve. I'm at 17 initial, 31 total in really early, like under 2500. It knocks at WOT on 91. A mix of 110 and 91 cures the knock, but I want to make it street friendly. Some of the responses I'm getting elsewhere suggest to skip the head gasket swap and concentrate on the timing curve and a cam swap. I just wish that I knew someone that had a near identical engine combo so I could get a better idea of which cam would work.
4000 70 Charger, stock body, 295 tire, 3.91 gear with a Gear Vendors OD.
440, .030 over 4.35 bore.
Ross Flat Top pistons, 6 cc valve reliefs, .017 in the hole at TDC.
Edelbrock heads, 84 ccs UNported, .039 head gasket.
.056 quench distance.
292/509 cam installed straight up, 1.6 rockers, 3/8" pushrods.
850 Demon VS, 85/92 jets, 3.5 PV
2" TTI headers, 2 1/2" exhaust