Price/performance , lower end Liquid coolers are not worth. The CM seidon 120V would perform more or less the same as a regular CPU cooler. The Stock coolers are good enough , but if you're overclocking, then another cooler would be needed.
The Scythe Big shuriken is one of the best slim CPU coolers and performs better than the stock cooler. You could swap the included fan with a Noctua 120mm fan for less noise