this can be considered as "almost equal" parameter product ?
if yes, shu has good prices
M1 0W40 and SHU 5W40 are both the top tier oils from two well respected companies, Mobil and Shell.
Both are ACEA A3/B4, MB 229.5, VW 502/505 and Porsche A40 rated full synthetics.
Shell Helix Ultra also carries API SP and BMW LL-01, but I'm not too sure where Mobil 1 stands with these two (a quick google says SN & no BMW for M1, but I'm happy to be corrected).
Plus in very cold climates the 0Wx (-40 C pumping) vs 5Wx (-35 C pumping) may be important to some.
I believe M1 is more PAO based and SHU is more GTL based.
But yes, for most applications I would consider them functional equals, and both of the highest quality.
I would happily use either, but I only use SHU because for me it's half the price of M1.