Thanks to everyone for the advice - one of the problems in the UK is that we don't seem to have the variety of oils (and eveything else) that you have in the US. Then the next hardest thing is to find out what basis the oil is (castor, mineral etc). Resellers just don't seem to know. I have been reliably told that Castrol R30 is a castor based oil so that's what I'm going with until it's broken in and then I'll switch to Castrol TTS.

I'll let you all know how I get on ......