My ds11 and dd9 had them as babies - and they were using them by the time they were the age of your baby. The daycare started propping dd in it when she was 3 months old and ds was already self-supporting his neck/back by 3 months. They both loved them and it provided them hours of entertainment so I could do laundry, prepare meals, wash dishes, etc. I always put them in the room I was in so I could keep an eye on them. My ds's was used the longest because after he started walking (the day he turned 9 months old), we converted it into a train track which he used until he was 3 or so. The one I got for dd is now in the nursery at church and still being used weekly. I think I got the $80-100 worth out of each of them - at this point I have no idea who made them.
Now my dd had a jumparoo - I didn't feel that was too safe - she was always grabbing the legs and I was afraid she was going to get hurt. On a plus side, any time she got constipated, I just put her in there and within a few minutes "it" was up her back.