On the topic of using these for travel, the simple answer is this: Don't.
They're heavy, tiring to run in, not good for running round corners, not good in the wet, take a while to get on and off, are difficult to store and carry when not in use, and they also make you sweat a lot XD
So in short, if you want these to have fun on, do some tricks, and generally do what we tend to do with them, then great, go for it, and you will lose weight using these.
If you want them mainly to travel using, and think 'hey, i could lose some weight as well', then i would advise a bicycle....
-Kaz
PS. Don't be put off, these are great fun, and worth getting if only for the fun factor of them, even if they are impractical during every day life.