I have a friend who makes confections professionally; instead of corn syrup, he makes his own invert sugar. Not sure if you want to go this extra step, but here's the method if you do:

http://www.chefeddy.com/2009/11/invert-sugar/

I've used Lyle's, or even generic golden syrup, for making candied popcorn. Works fine, but has, as Mr. V mentions, it's own taste, whereas corn syrup is pretty neutral.

You need to use corn syrup or golden syrup because they contain glucose or inverted sucrose. This is important because it inhibits the regular sucrose's recrystallization. Without it, you're liable to get a grainy mess instead of a smooth texture.

I've heard that it depends a lot on what kind of candy you're making. Apparently there is something unique about the process used in making corn syrup, and the resulting chemical structure of corn syrup, which makes it the best ingredient for achieving the desired results in some recipes. In other words, for some specific applications (and I've been unable to find any conclusive information providing any principled basis for identifying such applications), golden syrup may not work as well. But I'm with Mr. V . . . try it out on as small a batch as you can. Let us know, too! Good luck. ;o)

I love Lyle's Golden Syrup and have used it with good results. Just be mindful that it will impart its good toasted malt flavor to you confections. Maybe make a test batch before you go all out in making your candies.