In my opinion, I would never spend that much money on a single item that I can't use for combat or any real purposes, other than show-off. Also, instead of getting soul split, why don't you save up and get turmoil at the same time. I know way more people who have 95 prayer than 92 prayer. Goodluck with your decision.
I'm guessing most people posting don't actually have soul split. It's not worth it unless you get turmoil aswell. You're already maxed so it has no use unless you plan on getting 99 slayer. It's not all to great for bossing because you'll be doing overheads more than anything. Not to mention you won't find good corp teams without turmoil + overloads.