Wow... well if you can even find one it'll work no problem.
I own this flashcart and have had it for years.
It was very expensive when I bought it...
I suggest doing some light research and looking over the gbatemp reviews for slot-2 flashcards.
The card you are looking at is very decent. No slowdowns in games, but no realtime clock
and it only has native save support for sram and some eeprom revisions. It sticks out of the
gba by a few millimeters and is pretty noticeable. On the ds lite it probably sticks out about an inch or so.
This was a good flashcart in its time but its been superseded by many cheaper alternatives.
Like I said previously, check out some slot-2 reviews found here http://gbatemp.net/index.php?dynamic=8
and see what fits your needs.