Intek head gaskets are dirt cheap
I use the Stens ones where possible as they are a lot stronger than the OEM ones
After that I have some solid copper ones from Coppergasketsus because some heads just don't want to seal even after lapping.
I put that down to bad castings or bad post casting heat treatment it is possible to get aluminium to be harder on one side than the other,
BAck in the old days when you were doing a run the first 2 to 5 revolutions of the casting machine would all be considered as scrap because it takes that long for everything to get to full operating temperature ,
I assume I'll see oil squirting into the chamber on cranking?
No it will be sucking oilly crankcase vapour but you will see a gap hole or discolouration on one or both of the sealing faces.
Some of the tell tale signs of a blown head gasket are
1) White smoke coming out of the dip stick tube after the engine is turned off
2) knocking when the blades are turned on or drive engaged that smooths out
3) oil in the carburetter or air cleaner
4) oil dripping out the fuel pump brass vent
5) Plug oiling up / carbon fouling