I suspect a self amplified sub, integrated with the system, will yield a significant benefit. Without sounding precious, there are LOADS of car audio shops around but the car is under warranty. I’d feel far more comfortable with a shop doing the work who have done an Emira before rather than being a guinea pig. Cambridge have positioned themselves as a prestige option. I’ve had lots of aftermarket stereo installs fitted to lots of cars but never anything that already had a ‘premium’ system. Never anything under warranty either. On my Emira test drive I thought the system would be comparable to other upgrades in other cars. The HK system fitted to Mini and BMW for example. Both those systems sound OK, far better than standard, but they lack the ability to do bass. Some people are sniffy about the BOSE systems in Porsche cars. I was always happy with that. Dynaudio installed a good system in the Golf as well.
The KEF system sounds quite bright but the lack of a sub robs the ability to reproduce bass. I’m amazed the designers of the system were happy to put their name to it. It’s not nearly as good as it should be.
But- maybe the addition of a sub could be a game changer. Just want to follow in someone’s footsteps rather than blaze a trail. And £1500 for a sub install would leave me filled with self loathing.