Amazing device ! ...if he hasn't used one before he'll be blown away.
Really excellent quality for such a small unit...as you could well imagine there will be a noticeable difference between shooting in good versus bad light, it is after all JUST a camera so it too operates within the limits of its sensor & lens.
I used mine (the original version) a few years back when snowboarding in Canada and got some excellent footage of our group riding some amazing terrain....great times, great memories. The camera does really well...in good light it's exceptional, the stabilisation is surprisingly good and it's such an easy machine to use.
Tell him to bring lots of memory cards and to hit the record button often.....record for longer, not only will he get MORE footage which he can edit at any point but I found it easier to deal with fewer large clips rather than countless 10 second clips......and finally, record at the absolute highest resolution the device allows.
Recently sold my GoPro 1 and will be keeping an eye out for version 4 due for release in June/July I believe.