The kit was from Hobby Components, and at just over a tenner, I think it's fantastic value.
Bending the pins was a bit of a chore, to be honest - I'd never done anything like it before, so I had no experience of how to get nice and uniform bends. I knew that I needed a jig, and the instructions suggested that I could make one out of cardboard, which I did:
..but it wasn't really up to the task - so a lot of the soldering required two sets of hands - one to solder, while the other held pins together with pliers.
I've since seen a video (below) of a far better technique to use, which I'll no doubt follow when it comes to building my 8x8 rig - which itself will be pratice for an 8x8x8 RGB rig I want to build - which is going to happen once I've saved enough money to buy all the components - RGB LEDs are expensive.