My strimmer is like that, they shout about fast charging but it's not very fast when you have to wait an hour for it to cool down.
The 305a Fogstar eco at £499.99 looks appealing….
Drift ECO 305Ah 12V Leisure Battery
The Fogstar Drift ECO is your gateway to reliable, budget-friendly off-grid power. With a superb 305Ah capacity and 3904Wh of usable energy, the Drift ECO is perfect for powering everything from leisure applications like camping and caravanning to professional use cases like solar energy storage.www.fogstar.co.uk
Effectively what I have, albeit smaller capacity, with a Sterling lithium (which is unheated but inside the van so if I were trying to charge when it's cold outside the van heater would have put something in) where the bluetooth to the BMS doesn't work so I can't check the battery itself, and only know it's SoC based on using a Victron SmartShunt. As far as I can tell for 4 years the 120Ah battery is fine.
If you add a Victron shunt to that, I think you would be okay, you need some method of knowing what the SOC is, as voltage won't tell you much until it is pretty much flat, the shunt also needs setting up correctly for it to be useful.
Very few BMS problems, I think that I was just unlucky.
At £149 difference in price per battery? I would need 4 x 105Ah batteries bringing me up to £1476,
whereas for 2 x 305Ah without heaters or Bluetooth, (which we don't need), I'd only be at a grand, all but tuppence). 
I would say yes based on reading numerous threads this week and looking at numerous different solar set ups which are sold by reputable companies and I can see what sizes they sell with what what equipment. I almost feel like an expert just without the knowledge.
The first number is the maximum input voltage from the solar panels, the second number is the maximum amps it can deliver if you have sufficient solar input. SOC = State Of Charge.
IMO if you get that battery you're going to want to get a SmartShunt ... so factor in the extra £99
Correct
Whilst I agree with you in principle, the MANY discussions I've had with people at shows etc has me thinking that not knowing is a big deal to loads of people. For example (as I said to Lenny), not knowing if you'll wake up to no heating. So many people ask me if they will be able to see what's left in the tank if they upgrade to lithium ... always a smile and relief when I say "Yes".
Lithium batteries provide an almost constant voltage until they are almost flat so a conventional volt meter type display is not of much use in determining the state of charge, shunts count amps in and out so are more useful for lithium batteries.
I have found my Victron BMV useful for keeping tabs on the state of charge which is useful. The bluetooth battery bit that I am less sure about is the cell balance figures, which seem to cause lots of concern. I know that having these figures available I am likely to be checking them regularly and worrying about any disparity. I know the BMS will be actively managing the balances on my battery but being a worrier I will probably still obsess about them. Active cell balancing seems to be an extra on some batteries which surprises me because I thought that was one of the basic functions of a BMS.
It shows on your phone or tablet. Here are my BMS screens at 09:30 today.
As far as I am concerned a leisure battery should be maintenance free. My first LiFePO4 battery was a Relion and it came with only a + and a - negative terminal . It looked after itself perfectly well for 6 years without any noticeable loss of performance.
I did monitor the battery temp sensor on our system over the winter, but the data has now gone from VRM, from memory the batts did not go below three degrees on the unheated van, with the batteries in the garage. Charging stops at 5°c as set in the Victron kit but would have been within a safe level of charge at that temp in any case since solar is pretty poor over winter. It was a mild but wet/cloudy winter on the south coast. I don't remember ever seeing the batteries at or below 0 for the last couple of winters, or the SOC going below 60, and since every now and then I give the van a run for an hour or two, once warm the battery gets a good top up then. Actually on a sunny day it warms up a little as well.
Schrodingers battery!
That is the point I am making, we shouldn’t have to worry about cell balancing but there are now batteries without active cell balancing.
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