Little Busters was an insanely influential VN for me, and I love it to death, but it's flawed to the bone. It really depends on how much you like Key's approach to storytelling, magic, whatnot. It doesn't have much of a plot, alot of the drama is kinda whatever, and the heroine routes range from god awful to decent at best, imo. But, the true route is basically made for people who believe in friendship and the concept of it. It's rich with power of friendship and such and such, and to alot of the english fanbase, extremely heavy on the emotions. So, take it as you will.
(Honestly my biggest issue with Little Busters is that all the routes choose to focus on very ill-developed romance instead of the central theme of friendship. It makes the message really inconsistent.)