OEM spec 5-30 vs 0-40

[Boston01X5]

Hey guys was curious what you run for oil. When I first bought my E53 noticed lifter noise on startup and asked a friend who knows BMW so I switched from using factory spec 5-30 to 0-40 and it seems to help with the noise. That’s what he recommended on higher mileage E53 4.4, from what he said it is thinner on a cold start and is thicker in hot conditions vs the 5-30. I live in New England so temps range from 100 during summer and 0 or colder during winter. Been running 0-40 for about 8 months and time for oil change. Seems to have worked well. What do you guys recommend going with next oil change? And are there any downsides to running 0-40?

Thanks