Liquid Cylinder Head Gasket Repair

Hello fellow Land Rover fans,
18 months ago I bought a basically sound '95 4.0 GEMS P38 in need of some TLC. Running on petrol/LPG. I have renewed exhaust, lambdas, coils, HT leads, plugs, MAF sensor and various bits in the air suspension. For a while the old girl was running sweet as a nut.
I soon started to notice a slight untraced leak in the cooling system. It would lose half a litre or so over a 3 hour run. Thinking the leak might be from the inlet manifold gasket, the only place I couldn't see, I set to work and changed it. To no avail, the problem got worse and I started to notice creamy gunk in the oil filler/ rocker cover. Oil on the dipstick is clean. Now when it runs with the oil filler cap off I can hear dreaded chuffing noise.
I'm pretty sure just one of the cylinders head gaskets has blown. However, I'm not getting any over pressurisation in the cooling system.
My question is, has anyone tried Steel Seal liquid cylinder head gasket repair. I noticed this stuff on the counter of my local GSF store when I was buying bits for the Mrs' VW. Chap in the shop says it works, but then he would. Apparently it goes in the coolant and after warming the engine up a couple of times, seals the leaks.
At £35 a shot its not exactly an expensive fix and certainly works out cheaper than a decent gasket and head bolts set. I would tend to trust posts on this forum more than those I have read elsewhere. I have read and acted on some very helpful advice and tips here already.
If I can't get any enthusiastic feedback for the stuff I'll just have to knuckle down and strip the heads out. Got plenty of time on my hands, another 5 weeks off work for radio therapy.

:welcome2:

Sorry i cant give you any ideas on the gasket repair stuff as i have never used it ,,but my one question would be ..how long will it last ( if it works ) ...if you have 5 weeks to burn
enjoy yourself,,,do the heads,, you will thank yourself for doing it ..and possibly save a chunk of dosh.. thats my two pence worth.. :welcome2:

Thanks Aleric,
Don't know about 5 weeks to burn but after another couple of weeks of gamma ray burns I probably won't feel much like swinging the spanners.
I surfed the internet on the trail of Steel Seal yesterday. It appears to have been around for some years and may not be the magic bullet I hoped it might. Clutching at straws I guess.
Anyway, the sun was shining and with nothing better to do I donned the overalls and vinyl gloves and set to it. Couldn't believe the gunk in the rocker covers. I got the rockers off before bad light stopped play on the drive. Another fine day forecast tomorrow so I'm actually quite looking forward to getting to the root of the problem.
Thanks for the welcome and encouragement, getting down and dirty was just the job to take my mind off the other s**t.

Well the gunk in the rockers might well be down to the EGR valve ,,if its still in operation ,,get a blanking plate.that`ll stop the gunk build up.
I know what you mean with the other s**t had family go through same ,,,enjoy doing the heads..

K-Seal will seal it