Is it possible to keep your number if you move to sim only? If so which would you recommend? Nowadays I barely use the phone so sim only seems the way to go.
Both of those companies are fine, I'd go with the second one simply because they use EE and I get better coverage in the places I use my mobile.
Neither are contracts and can be cancelled any time so are worth a go :)
Pointless paying more if you aren't going to use the benefits.
I've been on the same deal for years now, not bothered to change, as it suits me. So not up to date with the market and can't really recommend any in particular.