Everybody is different. My friend swears by maeng da thai. I prefer bali as maeng da seems to only give me anxiety but not energy. Bali makes me energetic while he would be about to fall asleep from a dose.
I'm almost certain my source would have decent quality maeng da, They always have good quality Bali. I guess if there isn't a huge difference in strength it isn't worth paying almost 3x the price of Bali per oz.
Supposedly there is no Kratom growing on Bali, it's just a name that came from the fact the distribution was done from Bali. Sometimes the so called Bali is actually Borneo Red Vein, or a mixture of it with another strain like a Sumatra Red or white Vein. In general Reds are more painkilling/ sedatives and the Whites are more euphoric and stimlating. Although for me it doesn't work like that I find Borneo suits me best for euphoria.
Green Malay has the best of both worlds and some of it's own characteristics. Maeng Da is overhyped and pricey imo as it does nothing for me the other strains do better. Another greet one was Super Sunda which was almost twice as strong and longer lasting as Borneo. Good luck.