I find it pretty roomy for a 2-seater roadster, minus the backseat on my Lexus IS, I feel the front cabin of the Z4 is bigger. It is fun to drive, not surgical in the corner but it won't disappoint but it best for cruising for sure, if you want something that will have more kick and neck snapping speed, go for the 35i version. It's surprisingly comfortable for cruising and perfect for SoCal weather, you might enjoy it as much if a place that rains and snows a lot.
In it's category, I say it is right about in the middle and a combination of driving experience and cruising fun right between the SLK (more cruiser, less driver) and the Boxster (more driver, less cruiser).
As for it looking girly, personal opinion I guess. I love the classic roadster look (long hood, short rear) and some might even argue it's a bit phallic so does that equate to being "girly"? Up to you to decide.
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