I love greatswords and I have used the Bastard Sword in most of my runs for early game.
Pro's: 1 Early accessible, 2 Easy to get, 3 cheap as fk only 3000, 4 Not Unique so you can obtain more to experience with diff builds, 5 quite fast for a Greatsword, 6 Low Stamina costs, 7 easy upgrade with titanite, 8 Nice early game damage, 9 Swag level over 9000.
Con's: 1 Shorter range then most greatswords. Kinda falls off in late game. Slightly due to damage, but mainly because the low range will pay its tole in late game as the enemies become more difficult.
Overal, I say that the Basterd Sword is a great weapon. One of the best weapons in early game, and not that hard to use. So I deeply recommend this weapon for beginners that have an interests in Greatswords.
Later in the game, you may want to replace the Basterdsword for something more mid/late game, but until the first lord of Cinder you are good to go with this weapon. YW.