Portal (on The Orange Box) vs. Portal: Still Alive (XBLA)

[JK Ferret]

Apart from the achievement sets, is there any difference in the games? I've got TOB and finished Portal fully (and loved it - I now understand all the in-jokes on the forum!), wondering if there's any extra to make it worth spending 1200 MS Points on Still Alive.

[PeterStoba]

It has 14 new challenges based on the flash version, and more achievements.