I used to work for a party rental company that rented out professional-grade inflatable bouncers. This one costs a fraction of the cost of one of those -- in fact it doesn't cost much more than renting one -- and it's built on the same principles. What's different are the materials. If you understand what you're getting, I think this is a great option and well worth the money. If you're expecting the same thing the professional companies have, you'll be disappointed.
So the three differences between this product and the expensive ones:
1. The size -- this is big enough to hold 3 or 4 kids comfortably -- we had 7 in it at one point and it worked fine but was fairly crowded. The professional ones vary in size but all the ones I've seen are bigger.
2. Both are made of vinyl, but the vinyl on the pro ones is more durable (and it tends to be smooth, while this one is textured). I was pleased with this product. I believe it would stand up to regular home use fine for quite a while, but it's certainly thinner and that would make it less puncture resistant than the pricier pro ones. On the plus side, it's only ~35 pounds, instead of a couple hundred pounds for the ones you get from the party rental companies.
3. All of these leak air at the seams -- this product and the pro grade ones. That's normal. The air blower is continuously running to make up for it. More kids, or heavier kids, or harder jumping will push more air out at a time, and requires a stronger blower to make up for it. The blower included here works great, but is less powerful than the more expensive higher end models come with. 7 and 8 year old kids noticed a slight difference here -- not quite as bouncy -- but it didn't keep them from having a great time. If you're looking for something to handle teenagers or adults, this probably isn't up for the challenge.
I was very pleased with this product, and for only $50 more than renting a bounce house for a weekend we now own one we can use again and again. Younger kids didn't seem to notice a difference. In fact, one of my kids said it was just like the the others. However, if you want something for older kids, or you're expecting the exact same thing you've seen at businesses, you may be disappointed. This is a home grade unit, but a nice one at a fraction of the cost.