When did your kid start using a jumperoo?

[Lupe]

Hi
My DS is 15 weeks, and he loves to stand up and is very mobile (started rolling over at 10 weeks, front to back and is seriously practicing back to front, which he just needs a little push to do). He also needs a continuous supply of entertainment. I had resisted buying any more baby gear because our 2 bd apartment is turning into a baby explosion but since some friends with kids told me that jumperoos are lots of fun for babies and most important, makes them tired (it is hard to put DS to sleep) I got one.
Is DS to young for it?
He does not seem too sure what to do in it. For starts he is too short so I put a big book underneath it. He likes it if I make the thing bounce, and it is interested in a couple of the toys. But by himself he taps his feet, no jumping and gets bored and wants me to take him out. Granted he has been in there 2 times, am I expecting too much? how long does it take babies to figure it out?
He wants me to move the thing and that defeats the purpose of having it so I can do something else while he is in it

[BabyBearsMom]

DD didn't start the jumperoo until she was about 4.5-5 months and honestly we only used it for about a month because she was crawling at 6 months and had zippo interest in staying still. They need really good head control before they start bouncing and I wasn't comfortable with DD's until she was over 4 months. It took her a while to get the hang of jumping in it. We got a lot more use out of the exersaucer, actually. She used that from 12weeks to 6 months and really enjoyed it. I think that every kid is different. Some like the jumperoos and some like the saucers and some like neither and some like both.