Hey, I recently got this N-Charge II system and thinking about getting rid of it, due to its size and weight. Not really a big draw back, but when I can just get two extra powerbook 15" for $129 each makes no sence to have this one. Size and weight is a big difference from the N-Charge system compared to 2 Apple Powerbook batteries which is smaller and lighter. Has there been anyone who has had any good luck using these so called high capacity external batteries? Do they really provide that extra time or even last longer than the regular batteries? I've only seen 2 posts on these, but not with the answers I'm looking for. thanx in advanced