[Closed] Giff Gaff and mobile broadband?

My parents've got an old 3 dongle which doesn't get anywhere near as good reception as the new one 3 sent them. So 2 questions.

1) will it be 'locked'
2) will any of the £20 ones on ebay be any good?

Need/want broadband for 3-6 months but can't (economicaly) get a phone line.

Is there an Orange equivalent to giff gaff (which I think is O2?) as they seem to have better phone signal here, I know O2 is a little ropey on iphones so will need all the help it can get. But a good dongle makes a difference, my parents can get a 3G signal and almost normal broadband speeds on their new one, the old one was barely better than dial up, they're ina borderline area accrding to 3 (a normal phone cant get signal, but the dongle does if placed int he windowsill on a long USB lead).