I know nothing about that company but I can definitely recommend the one that I'm with: Asda Mobile.
They use the EE network, so you'd get the same coverage with Asda Mobile as you would with EE.
Their customer service is superb, with their phone lines answered instantly by friendly, knowledgeable staff (in the UK).
If you don't sign up to their 'bundles', you pay 8p per minute for calls and 4p for texts. (Non-bundle credit doesn't expire unless you don't make any chargeable calls for 180 days) .
If you only use your phone for emergencies, you could pay £5 per month for a 'bundle' providing 125 minutes of calls (plus 2000 texts and 250MB of data).
£7 per month would get you 300 minutes of calls (plus unlimited texts and 1GB of data). So that's an average of around 10 minutes per day of call charges included.
£10 per month, which is what you're considering paying anyway, would get you 600 minutes of calls (so that's around 20 minutes per day on average), together with unlimited texts and 3GB of data.
[There are also 'bundles' at £12, £15, £20 and £25 per month but I can't see that they'd be relevant to your needs. Although you don't currently use your smartphones for internet access, Asda's bundles would allow you to do so, with no extra costs, if you ever chose to do so. They even double up those data allowances if you set up regular payments from your bank].
https://mobile.asda.com/