I've used Magix Audio Cleaning Lab to transfer some old tapes to CD. It seemed to work quite well, but I had an uncomfortable feeling of not really knowing what I was doing. As with most software there was the feeling of oodles of hidden functionality that you need either a degree in IT (and sound editing) to get at, or the patience and attention-span of a saint (I have no patience with anything these days - and the attention-span of a gnat!).
I also experienced several annoying and initially baffling glitches. For example, one of the old tapes consisted of an interview with a trad. singer. At one point the great man paused to consider his reply to a question and the program 'decided' that the interview was at an end and stopped transferring data to my hard disk. Needless to say I was in the kitchen making a cup of tea at this point and didn't notice what had happened. Consequently I had to start all over again and sit over the computer to restart the program when the tape got to the pause. I'm sure there are all sorts of ingenious ways of getting round such problems - but (he said peevishly) I just want it to work first time ... !!!