We stayed in Mazarron Country Club last August and visited Puerto de Mazarron a couple of times. I think its a lovely little resort, mainly a Spanish holiday destination rather than attracting lots of Brits, although you will find some there. It was quite packed in August during the evenings, but probably less busy at other times. It has a nice sea front promenade, cant really think of much else to say about it really. If you land at Murcia airport its less than an hour away. I would go there if offered the use of an apartment