Now ive started using oil in the Daytona, Ive become a bit of an oil geek.
I have heard good reports of British organic rapeseed oil - any ideas?
100% synthetic is a bit ott on some bikes. Check your booklet and use the reccomended oil as per manufacturer. Job done.
I’ve tried everything from the the oil the manual recommends at 50 quid, oil that Triumph currently recommend at 45 quid, and Halfrauds chip oil at 20 quid. I have yet to notice any discernable difference between any of them.
If you don’t like doing oil changes regularly (you may have proved that already:)) then use Fully Synthetic and extend the intervals otherwise use what the manufacturer recommends at the regular intervals.
You might not notice but your engine might over time. The weight/viscosity is the important bit, I use the expensive 10W60 fully synth my manual recommends - still cheaper than new cam shafts 
The KTM gets 10/50 in winter 10/60 in summer . fully synth . This change will be Motorex 10/50 recommended by the manufacturer . The Intrusion , will be getting the same 10/40 diesel engine oil as the tranny van gets . My budget daily bashers always go on the diesel oil ,you can always get it and its available very very cheap 
Whatever you decide, for effs sake don’t buy from Halfords.
I bought 4 litres of the recommended spec. fully synthetic oil (but Shell, not Agip) on line, delivered to my door, for slightly less than price that Halfords would have charged me for 2 litres of Mobil.
(My friend who runs an independent service station reckons the best thing about Halfords oil prices is that he can charge customers just a little less, so no arguments about price, and still make 200% profit on the price he pays for bulk drums. Shame he doesn’t hold stocks of fully synthetic of the right spec.)
True, I don’t think I would trust Hafrauds in there for any length of time, I would guess it deteriorates more quickly.
Every now and again Halfords have a 50% off oil sale. At that time, it comes down to about the same price you can get the same oil from a decent motor factor, meaning that if Halfords are more convenient to your location and they happen to be half their normal price you should buy from them…
I buy my oil off ebay, best bargains and it gets delivered to your door 
Can you be certain it’s genuine, though?
+1 It’s the best there is.
Why do you think that’s the best oil there is?
The best oil is whatever oil spec is recommended for your bike.