Useful post - I had just recently been considering 0800 vs 0845/0870 (especially as there are sites about hating 0870) but can see that getting calls from a mobile could really sting the recipient.
I know some mobile networks/contracts are now including 0870 (and Ofcom blocks 'income share' so business no longer has any benefit from keeping someone on hold, so perhaps the general hatred of 0870 will die out soon)
Seeing the charges for mobiles had made me completely rethink whether to bother with an 0800, with or without any monthly minimum!
Thanks Vampiera (even if you didn't expect to put someone off using 0800 !!)