Praa Sands is a quality wave when it's working. Often provides a really heavy, barelly wave near high tide, breaking close to the beach. On the down side this is probably the most popular beach on the south coast and get's packed whenever there's a south coast swell and northerly wind.
Generally the best wave is right out in front of the Sand Bar at high tide although at a lower tide there can be some decent waves closer to the cliffs. It seems most days not much goes no between this end and Hendra at the other end on terms of waves.
Praa handles a reasonable size swell, I've seen it surfable up to about double head high, but it is heavy. The classic story is about Pete the Yank wiping out, thinking where's my board only to find it bungee-ing back, tail first into his eye - ouch!!