All the above oils are adequate for the application . Use up what ever you have use the lighter grade during colder weather .

if you're talking about the oil in the pruner head? if so, bar oil would be better.

I was able to find the manual for this tool HERE. The OP must be asking about the chain bar oil as the manual calls for 30wt or low viscosity bar oil and specifically calls for two stroke syn. oil for the 'petrol' (English, you know).

Regular chain saw bar oil seems viscous to me, so I assume the oiler in this unit is not designed for regular bar oil, but rather needs a less viscous oil like 30 wt. I personally wouldn't know if the newer syn. oils have similar viscosity to 30 wt, but I also know that sewalk or knuttle wouldn't steer you wrong.

Bar oil is tackier to resist being thrown off the chain . In this application it would most likely cause plugging issues , thus the Sae 30 which is the lowest Viscosity that is advisable . Use of of multi grade 15-40 in summer , the synthetic 10-40 would be prudent within colder ambient temp conditions to enable better flow within the prunerhead . FYI back in the 50,s to early 70,s prior to modern bar oil invention Sae 30 was used universally within bar oiler systems . However today I run Bailey,s Motion motion which has tackifiers rust and anti galling additives within a canola oil base .

I just use the canola oil and sometimes peanut oil in my little saws. Whatever the wife is throwing out of her kitchen.

I usually refrain from peanut based products , hard enough to keep the kids at the wood site without allergy issues giving them xtra leverage .

I know it is hard to resist the whole green pressure thing. Still, it is good to know you are doing what you can in the face of adversity.

Peanut oil is excellent for deboning moose carcaus when used as bar lube with elect chain saws or small gas units only in the Great White North !

Thanks guys for all your advice.......I'll tread (cut) carefully and see what happens!