I have tried the Motomaster in other vehicles, and it does a good job, but I noticed with the Valvoline in the same vehicle I burned less oil and did actually got a hair better fuel economy.
I also had a bad experience with Motomaster once with their synthetics, almost as if the wax had settled out from the mixture and left a film on the bottom of the bottle. This was not an old oil either. But I am sure that Shell has solved that problem since I haven't heard of this issue since 2004.
Keep in mind, these are both high quality oils; Motomaster is made by Shell and of course, Valvoline by itself (Ashland). For the price, I would go with the Valvoline, is it really worth an extra $3-4 for 270mL? I don't see it. For the price, I am recommending the Valvoline SynPower. It also what I use in my Big Green Monster.