For £25 I thought it would be a bit thicker and add more protection to the speaker. It fits well mind you and wont slip off but is only really good for stopping the speaker getting scratched.
I only took it to a couple of gigs and the plastic is very prone to scratching (there are already several marks all over it and i was very careful), so one of these is preferable, but I would have preferred one with padding as a speaker that size has a tendency to fall off of kit when loaded.
All in all I think for a bespoke slip it may be pried OK, but I would look to make your own with foam if thats possible. The one i have on my Yamaha DBR12 is custom and is very protective. This cost £70 though!!