Welcome back. Don't know where you have been but Giffgaff has always been the best option for me until now.
If you have a bank account, Smarty and Voxi are the now best options to be honest however my stepson has got me on a super half price deal on o2. £12:50 a month for unlimited calls, texts and 40gb data so for me it's Goodbye for now.
I may be back when offer ends.