Scirocco Central

First time post so I apologise if this has been covered already

I've got a 2010 Scirocco Gt Tdi 170, when I brought it, the drivers side speaker wasn't working so I replaced both front door speakers with JBL GX600C 6-1/2 Inch 210-Watt, to my surprise they didn't sound too great, they sound decent but nowhere near the expectation I had for aftermarket speakers, and no where near the speakers in my friends car (he has a 2001 mini). The bass and low end isn't nearly as strong as I expected, the drums aren't as deep as I expected and the audio gets distorted at high volumes, like really distorted. I had a 2006 golf previously and the sound quality was so much better. I figured that replacing the headunit would improve this and besides i need to upgrade it something that is compatible with reversing cameras anyway (my friends speakers improved significantly when he installed a new headunit).

I've been recommended Kenwood Car Audio DMX8020DABS 7 but they are like £500-£600. What head unit would you guys recommend?

Thanks in advance

I have an Erisin es8715v 8" android head unit.It looks oem,sounds really good with dsp and is endlessly customizable. I bought it direct from Erisin for £200 and saved @ £50.