Going from a 335i to a Mazda Miata?

I own a BMW 335i with terrible reliability issues. Of course I'm not going to tell the dealer I'm trading my car into about the issues, but it is the main motive for me getting rid of the car.

The car is still under warranty but it's paid off fully. I estimated the value of the car to be $30,000 based on Autotrader searches and the KBB resale value.

I'm actually thinking of going for something Japanese because I know it'll be more reliable. The only Japanese cars that interest me are the Miata and the Honda S2000. However, it's tough to find a Honda S2000 in good condition and I would much rather prefer a brand new car over a used one.

Do you think adapting to a Miata will be easy?

I rarely drive and I don't carry lots of groceries. I live alone & live in a big city. I usually walk to the store to pick things up. My car only takes me to work and the occasional road trip with my boyfriend.

So basically, I know the size of the Miata is not an issue. I'm just concerned about the comfort and build quality.
I test drove one and it seemed fine (in fact, it was so fun to drive that I didn't want to hand it back) but it was only for 30 minutes.
Added (1). Yes, I am aware that I might have to spend a couple thousand $ to trade into a Miata.

Yes, I'm also aware that most Miatas are stick shift. My current car is stick shift so it's no problem.
Added (2). The wind noise was slightly louder than my current car on the highway but it's not significantly worse. The car lacked a backup camera too but it's the size of a couch so I doubt I'll even need one

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