850R - What oil?

[D_T_W]

Car will be due an oil change before Christmas, when i bought it i had it serviced and the mechanic put 10w40 Semi Synthetic in it as he thought that's what was reccommended in the manual.
My preference would be to put fully synthetic in it, but i know some engines don't take all that well to fully synthetic.

Advice much appreciated

[P10DGR]

I use 5W 30 shell helix fully synthetic in my v70r, supposed to be best for them and it's what i've had recommended to me by the guy that tuned it, as you should know it's had a little work done.