Yes, extremely good value.
I took EE to CISAS when they increased contract prices in April and won at the adjudication and was allowed to terminate my contract and they were instructed to supply my PAC. I moved my number over to giffgaff as a temporary measure in May while I decided what to do.
I'm still there, I have found coverage and service as good as (or better) than EE in use. It's incredibly good value, I pay either £10 or £12 for the month, depending on how much data I expect to use (£10 = 1GB, £12 = unlimited).
International calls are cheap and freephone calls are free.
Customer service is not automated as someone said, it's online, either via the forum or a direct "ask an agent" link that you can use.