I'm up in Canada and I have both the Good Nite Lite and the Gro Clock. There's pros and cons with both of them.
I bought the Good Nite Lite a few years ago as the Gro Clock wasn't available in North America at that time.
http://www.goodnitelite.com/ This one is like a big night light and you have to plug it into an outlet. So you need to have an outlet in a suitable location in the room in order for LO to be able to see the light. What I did was plug it into an extension cord and put the light on DS1's book shelf across on the other side of the room from his bed. I had to prop it up leaning against the wall on the top of his bookshelf so that he can see the moon and sun. Originally I had it plugged into an outlet near his bed but it was too bright so I moved it. It casts quite a bit of light so now that he's older, I don't have it propped up anymore on the shelf, it's laying flat, so he can still see what colour the light is but not the actual face on the light. I find the Good Nite Lite to be easier to "program" than the Gro Clock, but it could just be me, I'm not good with gadgets!
I just started using the Gro Clock with DS2 who is 19.5 months as we've been having EWs due to the 18 mth regression. I found the Gro Clock was more frustrating to program...it takes me many attempts to get to the screen I want...but it may be just me! As others have said, the blue light can be quite bright, and it does have the option to dim the light, but I still found it bright on the lowest setting, so I turned it off. (You do this by setting the dimmer to 0). But this means that you don't see the moon/blue light at all at night time. If you need the blue light to help tell LO that it's bed time, you'd have to change the setting and then turn it off later in the night if you didn't want it on all night. The other thing I don't like about the Gro Clock is that you have to "set it" each day so that the sun will come on in the morning. (Kinda like setting your own alarm clock). If you forget, the sun doesn't come on in the morning. This has happened to me! I find it annoying that I have to remember to turn it on each day, but maybe as I use it more, I'll remember

I didn't know that I had to do this when I bought it.
With the Good Nite Lite, you program a time for the moon to come on at night (I set it to be on when we come up for BT routine) and you set a time for the sun to come on. You don't need to re-set it every day.
I hope this helps!