A. Bonnell spring mattresses have a mesh of springs which are interconnected. They provide bounce and resilience and increase the durability of the mattress. Bonnell spring mattresses provide a great sleep experience to the ones who are looking for an entry-level spring mattress. Pocket spring mattresses, however, feature pocket springs, which are individually cased springs. They move independently and do not allow movement to travel from one end of the mattress to the other. This way, the sleep movements of you and your partner do not disturb each other.