[Techworks]

I'm trying to choose between the 50i and M50i. I like the aesthetics of the M50i and a little extra HP would be fun on occasion. However, I spend ~2 hours per day on the highway, so I'd like to understand the difference in noise at cruising speeds. I know I would enjoy the power and noise on short bursts, but on my daily commute, I'm looking for the quietest and most comfortable option.

1. Is M Sport Exhaust on the M50i always loud? Does it have a baffle or moving parts that are automatically tuned to quiet when in Comfort?
2. I saw one review of the M50i that said exhaust sounds are piped in through the speakers. I know BMW has done this before on other vehicles, so I assume it's true here. Is this a good assumption? Does the amount of noise amplified by the speakers differ between Comfort, Sport, ans Sport+ modes?
3. If the M50i has exhaust sounds through the speakers, does the standard 50i also have them?
4. Aside from the M Sport Exhaust, are there other mechanical differences between the M50i and 50i? Is the suspension of the M50i as comfortable as the 50i when in Comfort mode?