The Motorpro 20W-50 is cheap SHITBOX OIL, for if you need to do an oil change on a shitbox that you don't really care about. Do not use in cars manufactured after 1996, you'll have a sludge of a time.
Shell Helix 15W-40 - https://www.kmart.com.au/product/shell-helix-hx5-15w40---5l/…
Find in-Store or $3 C&C ($0 with $20 Order) only.
You certainly make it sound tempting!