To answer op's question, since you have maxed melee I'd say get rapier. A friend of mine recently got cls, and I recently got rapier. we decided to go against eachother in tasks, boss hunting etc. to see which weapon was better. Neither of us have access to extremes, but he has turmoil whereas I do not. In every slayer task, I beat him by about 10-20 kills for tasks of about 100 monsters with myself using piety and him using turmoil. Using the exact same setup for bandos/ zammy, I ended up with a few more brews/rocktails than him in the end. In everything we've tried, rapier has beaten out the cls. This may not apply to someone with lower stats than you and I, but at your level you must certainly want the rapier.