Long time lurker and have just completed a new install of mine.
The Model 3 has by far the best factory system I've heard, but never pulled me in on an emotional level. Flat dry sound.
I pull some of my old parts together and had a brand new set of Boston Acoustics SPZ50's sitting on a shelf I forgot at my grandparents for almost 10 years.
I've been a big McIntosh amplifier user for cars for 20'ish years. Anyways, wasn't alot of work to do the setup and am very, very pleased with the sound. Not may folks will have heard the SPZ's from Boston back in the day, but they can match a high end Morel or Focal two way setup when done properly. They are truly a special speaker. Mine are the little 5.25 drivers, they have a huge 1.5" voice coil and 1" of excursion. The midbass and bass extension off these things is unreal and boston did design them for you to consider them as a replacement for needing a subwoofer in the car. Also not shown I've added a pair of Boston Environmental Imaging Tweeters. The SPZ's are 3 ohms rated for 150 watts, they take a lot of juice to move. . And my MCC404M McIntosh amplifier can deliver.
All of this was brought together with a JL Fix-86. Was doubtful on using an analog DSP summing device as it could skew the sound, but wow it worked well. Clean and flat and near unmolested sound. Highly recommended. The install was all done in the Front Trunk (Frunk) Onto the pictures and feel free to leave questions or comments.