Obviously real tennis >>>>>>>>>>>>>>>>> any tennis game.
But in absence of a partner to play with, Smash Court Pro 2 is the next best thing.
I haven't had in depth time with it yet, but so far I'm really liking the evolved game mechanics, a very nice step forward from VT2/SC1 (my favourite two games before).
Lots of new gamemode aditions too, some similar to Virtua Tennis stuff. The one thing I am still undecided on is the unusual event based Career mode - it's definately quite different then anything I've seen in a sports game before...
And yeah, graphics are better too, girlplayer faces are not butt ugly anymore (still not exactly appealing though
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).