(Another) Battery options - Solar with ASHP and EV to follow

Jtaustin316

Afternoon All, 

I've read through quite a few of the forum posts and found a lot of useful info/tips (and I've a fair idea of who to avoid...), but I'll continue to ask in case anyone has gone through the same/has useful thoughts/hints/tips;

I have a 16kW LG Therma V ASHP recently installed (to replace old Firebird Kerosene boiler)
Complimented with 6kW Solar PV Array (Longi LR4-60HPB)
Both installed within the past 3 months
Realistic consumption profile is looking at 600-800kW in Winter months and 300-400kW in summer (we've averaged 10kW per day since May/June with our system in situ, that's almost all utilised from dusk til dawn).
No current EV, though may well pick up a Tesla3, Ioniq or similar next year so capacity will be a thought

Previously we were content with the solar generating daytime system demands and covering 'dark hours' from the grid - but at approaching 60/70p/kWh (whichever you believe will be the end price) we're throwing away good leccy that we could realistically utilise with a battery setup.

Has anyone retro-fitted in a similar set up (or complimenting solar only)?  
Anyone who absolutely loves their kit?
Have been proposed a good looking Growatt SPA3000 setup and whilst the website and dealer side looks good, I've found little other than poor response time from Growatt themselves, unfriendly systems and generally negative reviews online.

Personal thoughts are - is the Powerall (13.5kW) worth the extra cash... 
Then again, is the Powervault (12kW) worth even more extra cash...
Or should we go for a low initial cost setup?

Happy for any thoughts/guidance/barking up the wrong tree, etc...

TIA
James