I love this little gadget! I bought two of them - one for me and my boyfriend for Spain. Having 2 USBs were ideal. We could charge our phones and our portable chargers or GoPro with this thing at the same time.
I never tested out a blow dryer or a straightener with it - it takes too long to maintain perfect hair in a foreign country :)
The only thing I semi-dislike about this gadget is that Europe's adapter wasn't "long" enough. In Europe, their plug outlets sink into the wall. While some outlets were okay, others were not.