Good value for money, fantastic customer service.
I use tello for ringing my dad in thailand, they are one of a few companies that do overseas mobile packages and tbh whilst they may not be the cheapest they have been totally stress free for me.
My dad is in thailand for 9 months a year and I phone him every other day, I have a £10 a month rolling contract which gives me 500 mins to thailand which is totally sufficient for my needs, To date I have not ever used up the 500 mins, unfortunatley the mins do not roll over.
When my dad is here for the 3 months a year he uses the tello international mins to ring his wife, that way I never have to cancel the contract.
I have phoned customer service on 3 seperate occasions and each time the customer service representaives have acted proffesionaly,friendly and have dealt with all my problems and queries with much haste, by far one of the best mobile phone customer reps I have had the pleasure of dealing with, They also answer the phone very quickly, in the 3 times that I have phoned each call was answered within seconds.
All in all a fantastic service, fantastic customer service with good value for money.