I took it only briefly a long time ago. First at 15 years old and a second time at maybe 35 years old. It didn't do me any harm, and didn't give me any memorable side effects, but wasn't particularly helpful either, at least at 35. However, my dad took it for years and said it was beneficial for him. The only side effect I remember him talking about was vivid dreams, and that he occasionally woke up punching his side table. He seemed to think that was buspirone related.

Your question about pill cutting perfection is best directed to your doctor or pharmacist, but I, personally, wouldn't sweat minor size differences, especially if I took exactly one pill per 24 hours. I do recall it being a unique pill in having two grooves (3 sections).

Don't drink grapefruit juice with buspirone. You'll surely see that in the paperwork.