Copper head gaskets

What is your experience of using solid copper head gaskets?

Are they just as good as ST205 'steel' gasket?

Tried asking on UK forum but not a single answer so I guess it is uncharted territory here in UK.

Car is a standard ST185 with currently blown gasket and our vintage guys get solid copper gaskets cut using water-jet technology and they seem OK.

No plans to increase boost (yet) so should I get a mate in the US to bring over a copper one?
(Or possibly send a pattern to the UK water-jet firm and get a batch manufactured).

what are the advantages of copper over steel as a gasket?

Many of the UK vintage racers (many are supercharged and are using methanol fuels to achieve high bhp figures) fit them because :-

Originals unavailable.
Commissioning new multi-layer gaskets in short runs is very expensive.
(I can get solid copper HG made in UK for less than a Toyota MLS gasket)
They are re-usable after annealing.
They are reliable when used with flat heads and blocks.

As regards the ST185 I saw that a vendor in America does solid copper items, hence my question trying to seek out someone in the States who had used one.

Useful info. at :- http://www.scegaskets.com/page/ICSvsMLS.html

Unless your blowing out MLS head gaskets (>1000HP?) there is no point even considering copper.
To run copper you also need to oring the block/head.