El problemo is, if you set it up to detect wi-fi it will always go looking for wi-fi networks (in preference to 3G) when you're away from home. And it'll probably find scads of them, all security enabled and useless to you. So in many ways, if you intend to use internet away from yr home network or other fixed location, leaving it on WAP is the better option. Oh, and if you do connect via 3G and then pass a wi-fi hotspot it'll drop the WAP in favour of the wi-fi - which will be security enables and useless to you. So all in all 3G is more user-friendly. (I have a SE smart phone too, an X10 mini). Unless you're a very heavy data user using 3G shouldn't be an issue - and as you've never used it before I doubt you'll be that data-heavy.