7's are worth every penny of what you pay for them and are of a higher build quality than projumps.
However Projumps are a bargain to get you into the sport and if your on a budget then you should go for these stilts, however if you have the extra money most people who have tried both 7's and projumps would agree that the 7's are worth the extra 100 or so you pay.
Then again, thats all just my opinion