Kwikload, as the name suggests, enables you to Save or Load yuor programs three times faster than conventional methods. Not only can it be used with your own programs, but it will also convert published programs as well. They claim to cut down loading times of The Hobbit to 120 seconds and Scrabble down to 136 seconds.
I think it's only fair to point out that they do not condone piracy.
With the tape, you get a 12 page (A12) instruction booklet. This is easy to follow and anyone with average knowledge of programming should find it quite simple. The only problem I found is that you have to buy a good quality tape as the smallest gap in the ozide will cause it to fail.
For the technical, the Spectrum transmits at 1500 baud and Kwikload improves this to 4500 baud. All program leaders are disposed of to improve times even more.
For data protection, what could be better? In fact, the whole thing is a little bit like upgrading your C5 to a 3.5 litre car.