In case anyone is interested and hopefully for others to avoid making the same mistake.
Before traveling this time to Crete, we were looking for a cost effective way of having mobile and internet for the first few months while we settle in, get tax numbers and address. We found advice on the web(money saving experts) advising people that the best way was to get a free 3 sim and load it with feel at home package. We have done so and opted for the £25 for 30days all you can eat data, 600 minutes anywhere and 3000 texts anywhere. Big mistake, although the package is available and ok to use, the coverage in Crete via Cosmote is rubbish. We hardly use it or able to use it unless you are in a big town and it's very slow.
What we found very useful and much cheaper was Vodafone. We got a welcome package for €10 thinking that we can use it as a supplementary local backup. This ended up being a life saver as we got 10 gig data and loads of other minutes included plus every other day we have been getting freebies (zoro) including data and minutes. The coverage is good everywhere we went in Crete (and I mean every where).
I am sure you good people must know of similar or better deals around but we were very happy with the welcome package from Vodafone and hopefully we will manage to get something more permenant soon.
Something interesting happened while in the Vodafone when we first arrived. A British guy was trying to top up a mobile and the guy in the shop refused to help him. Apparently and according to the shop owner, he refused to show him his passport or register the sim!! ... interesting! I wonder how he managed to get a Vodafone sim without registering it!
We had to give them a copy of the passport, fill in an application, Waite while he faxed the application to main office and then the guy called them to activate it. we then had to take a letter from Vodafone to the bank to add to our account for the one time code facility.
Hope this is of interest to others.