Now, these baby bouncer type apparatus are rather like Marmite. Some people love them, some people hate them. It can be a fun little activity for babies, who will enjoy pushing themselves up and down. Some people have left babies in the harness for too long, however, and that's not a good thing.
I got the blue version of this for my son. It always felt too stiff for him to manipulate properly, but even so he did like to go in it. I got one so he'd have a really fun, energetic activity during the winter, when there weren't so many opportunities to go outside. In the end we never did use it for very long. Just a few weeks in fact. He always preferred his baby gym, and his bouncy chair.
A friend of mine had a little girl who absolutely loved hers, and was in it at least once a day. She enjoyed it so much it was a real fight to actually limit her to just short bursts.
I guess the problem is, you never know what kind of baby you're going to have!