Are there any issues with the Empower Laptop Power Adapter that BA sells in its duty free catalog?

Specifically, I recall that the one that they used to sell had a warning in the duty free catalog that it would not work in Club World on the 777. (I'm curious as to why, but I remember it saying that.)

Anyway, I know I could get one cheaper at various stores, but I don't have the time to be bothered, and I need it next week, so I was just going to buy it on-board ... unless it has issues with club on the 777. (I'll be in First next week ... but a couple of weeks later I'll be back in Club on a 777.)

I know, I should have bought one years ago ... but until my most recent laptop, I've always used great old mini laptops that went over 8 hours on an extended battery. Just now I was getting everything loaded on to my laptop for next week and realised that the battery just wasn't going to cut it for my need to use it in flight ...

I guess I could always just enjoy the "First" experience ...