While this website can offer you an OK deal to recycle your old phone for cash, sometimes, for me, I just think I can get a better offer somewhere else for my mobile phones. On the odd occasion, (I think I'm the only one who has had this problem) is that they try to lower the price for the phone that was originally offered on their website.
One bad experience I had with them a few years ago, was that I went onto their website and found a good deal for my Nokia 8800 (the price I got from them was £55). I thought that it a really good deal that I got from them and within a few days, they sent me their envelope to my old phone in and sent it back to them.
Then, within a few days after sending my phone off to mazuma mobile, I went onto their website and found out that the price that they given to me was lowered to £30 and they had "claimed" to have sent me an email, telling me that they to lower the price because of some weird fault that they allegedly found on my phone. I argued my case to mazuma that the phone was sent to them in good condition and there were no faults at all because I thoroughly checked the phone before I sent it off to mazuma mobile. They said that they could do nothing at this rate and that I had to deal with what I have and of course I wasn't really happy with it but I had to accept their given price.