Pairing Sylvester and Speedy up in a cartoon is an obvious and effective teaming, when you think about it a bit. It does have the same obvious limitation the Sylvester versus Tweety shorts have-you know from the outset that no one will be lunch, even if one character does consider the other a part of their basic food groups. The reason these shorts work (when they do) is because of the gags involved and the background material. You hear a character singing a couple of lines of "La Cucaracha" (which are particularly funny if you understand Spanish), or you see the physical results of Sylvester trying to catch Speedy and it doesn't matter that Sylvester has a better chance of hitting the lottery than does of catching his prey du jour.
This is available on Looney Tunes Golden Collection Vol. 3 and is most definitely worth getting. I recommend the Collection without reservation. Highly recommended.