I think they've published a new edition every single year. And there's about 10 past papers with fully worked answers. But getting those isn't enough, there's more trials and older past papers on BOS (before 1990s even the 1960s..... lol but it won't be necessary though, they're too old). As long as you're doing loads of papers, plus know your stuff extremely well, then you should be fine!
Success One past paper book may have more past papers with solutions (eg. somewhere like 1992-2009). so it depends on YOU really.
