The ML system is also poor.
Based on my experience I would go for a high-end component speaker in the front, a sub in the boot, and a high quality amp (such as Hertz, JL Audio). If your budget allows it, go for some high end components in the rear also.
See my previous thread regarding aftermarket speaker upgrades.
I have a JL Audio 4 channel amp, JL sub and Hertz component speakers. The clarity, depth of bass, sharp top end and sound ima imaging are greatly improved.
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