I've never done it online, only at physical locations. People have said that you're much more subject to scrutiny/being cut off when you do it online, vs going to physical locations with both MG and WU.
have done it in person that last few years. tried it online a few weeks ago ($29 fee vs $8 fee in store) and was DENIED.
the seasoned bonus whorers can let you know the tricks of what to say to the online mg clerks.
you must call in to mg on all first time online mg transfers. they want to make sure it isn't a scam...that's when they scrutinize you. I would think once you clear that initial hurdle, you are gtg.