Have any Bankers had experience in changing a Micro Sim to Nano Sim?
There are tools avaliable online of course.
Is it worth it?
If the card is ' trimmed ' to much is the card useless?
No experience of SIM card cutting at all, but I reckon as long as you don't cut through the circuits it should be fine. A decent card cutter ensures it is the right size, no excess trimmed. If doing it yourself it'd be up to you to be careful.
Just phone your provider and request a nano sim! I tried a cutter from Ebay on an old sim card, wasnt happy with the result. Phoned Three on 28/12 got new sim through the door on 29/12! If you are putting it in a new phone, there may be a warning not to put a self cut sim card in as it may invalidate your warranty!