Isn't that the bugeye UK300 spoiler?
Welcome back Jumper
Oil (my personal preference) to 340bhp use 5 or 10w40 fully synth if you do road/fast road driving. Consider going to a 50 weight if you do a lot of track days or considering increasing power to around 390-400bhp. Genuine Subaru black oil filters are good filters.
I run 5w40 and reach 110 degress around Curborough which is relatively short bursts of acceleration. I wouldn't want to go much higher on a 40 weight personally, but then anything thicker and the oil won't reach optimum operating temperature during normal use. A mate runs 10w60 with almost 400bhp and his oil sits around 84 degrees after a back road blast. IMO, that's a tad too cold.