T.D.
the one we have is only good if you have like 2 maybe 3 kids, its the kind with a curve and a pool to "land" in. but its small and my 2 kids (3 and 5 at the time we used it) were about all it could handle. if the kids are bigger i suggest a longer one or one with a wider slipping field. as both my kids were half on the slipin spot and half on the grass. its not wide enough to suit me.
if i were throwing a bbq with many people i would invest in renting a bouncy house with water or something. the slip-n-slide just isn't enough for my extended family but a bounce house thats is set up for water will satisfy several kids at once and several age groups too