I have used both Airalo and GlobaleSim- both easy to set up. The latter gives you options of a UK/US/CA mobile number linked to your data allowance. You need to maintain the number by topping up, so unless you specifically need this it’s not worth the additional cost, since you can just use whatsapp or skype for calls. I think Airalo has the edge in ease of use since it has an app, so my preference would also be for Airalo