I've had fairly good experiences with this one:
https://www.amazon.com/gp/product/B00PA8PCNW
It looks like they've updated it since I bought it (new logo, spring carabiners instead of screw, etc.) but should be pretty similar. I replaced the suspension with whoopies and straps, though I wouldn't worry about the included rope stretching too much.
I've been very impressed with how durable it has been, but I wouldn't be comfortable with multiple people on it. For the price I definitely think it has been worth it, though depending what you're considering as a complete "system" 70 dollars may still be optimistic. Even using the included suspension you'll need a tarp and insulation and that can add up quick.