As there are no reviews, I'm going to say how awesome this thing is.
**Before you purchase this item, I'd recommend getting a second battery for your GSII.**
Since I bought this, I always have a fully charged battery. As the charging cable which comes with the phone is not very long, I hate having to sit near a plug socket to use my phone whilst it's charging. Now I have this I simply charge the spare battery, then switch them over whenever the other one is nearly dead. Granted I have to turn off my phone & start it up again, but the GSII does this fairly quickly. And once you've done it a few times, you'll realise how convenient it is in comparison to holding a phone with a cable attached to it.
The bonus of course is that fact that it acts as a stand for the handset too, and it sits very comfortably in it too. Some battery stands actually have a charge port for the handset as well as the battery, but I like the fact there isn't one of these as it means the phone can sit in it either portrait or landscape, so it's ideal for using when watching youtube or iPlayer. I would say that if you have a case for the phone, it may not sit so well in the stand if the case is quite chunky. For this instance I'd recommend the official "Cool vent case" which I have also given a 5* review.
The stand is in sexy black colours & is small & light enough to carry around in a bag with the charging cable if you wish. As it has a lid on the battery compartment, it acts as a case to prevent damage to the spare battery & it is useful having a stand available for example on a train.
I love it, & it looks good on my desk next to my Walkman dock.