You can drag me if you want. It was my first attempt at speaker pods. Three layers of 1" mdf. I wanted to match the Bugs paint. A piano black finish on mdf isn't easy. This is only the mids/highs.
Yea that bug I'm sure was loud but if you had the speakers aimed on axis towards the listeners ears you can perceive more detail at a lower volume making it overall less fatiguing.
You also could have a situation where the extra detail is overbearing in which a good eq can tame it down unlike being off axis which you would need to boost up. Turning down is always better than boosting up.
As far as imaging. You bug would've had terrible imaging. The sound staging being on the floor or behind you or both.
We tend to mount mids in the doors or kicks for convenience but if they were mounted inline with your ears at equal distance your sound stage would be nearly perfect.
But since we aren't mounting 6inch mids on the apillars wer compensate by mounting smaller midrange and tweeters up high and use time alignment to adjust the sound stage up or down between the low mount mids and the high mount highs. In addition to the already present left and right time alignment.
Typically mounting on axis helps reduce reflection distortion and delay as well. That distortion will always be there but you can minimize it by aiming on axis and by using soft panels. A carpet dash cap helps a lot as well as cloth seats and carpet floors. These all absorb sound waves and minimize distortion.
Personally I try and mount my tweeters facing the opposite side headrest so as to not whole lopside the sound stage to just the drivers side. I lose a touch of definition but not much.
All this in hand it really just depends on what kind of sound you want. I personally don't run pro audio especially not super tweeters