I havn't used the small cooked shrimp but I often use the medium size uncooked. I use half inch to one inch size pieces with a rag on the Clearwater( Idaho )with unbelievable success . The shrimp( peeled tail sections ) has out fished roe on several occasions. Pieces of shrimp( small prawn ) will stay good for twenty to thirty casts. Try that with roe or sand shrimp.