I own a T10 1GB pure that I purchased for a small 130 Euro. The T10 has a 20-30 hours battery life bonus compared to T30. I usually use my T10 in all sorts of activity, and if you're using it in agile activities accidents will happen, if you are using it for 6 months. I dropped mine from 1 metres or so outside, and it got a 2cm scratching or so, no more. I wouldn't feel very comfortable dropping the T30 or a IFP-395(
http://img.clubic.com/photo/00035021.jpg), that I owned, even with its nylonwrapper. I see the T30 as a more sophisticated and elegant player and a voice recorder, and the T10 as the more durable and long-lasting player made for heavy activity.
One isn't better than the other, it's a matter of what you need.