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What are your opinions on o-rings vs. gaskets for the cyl head?

I think I've heard o-rings are NOT the way to go, yet some are committed to that design - for example:
https://tsrproducts.com.au/collections/yamaha

Do o-rings seal reliably?

O-rings are also used on OMCs 60* V4s and V6s
Never heard any problem with them, in fact my 96 V4 is still running strong and never opened.

The TSR head I ran on my tohatsu 50 kept leaking with the O rings, although I've had issues with bad head gaskets that were aftermarket never had issues with genuine Yamaha ones

Thanks for the replies. Opinions seem varied, even before I asked here.

The thought came to mind that results may have a lot to do with block deck prep - maybe a lot of folks "DIY at home" without getting the block flattened properly. I can see this being more important for o-rings than traditional head gaskets.