Hi ,
1) The extra hole under the sctatchplate is the battery compartment .
2) They play really well , obviously not as good as a real Stingray . The neck is a bit flatter at the back , but soundwise , compared to my 2016 MM stingray almost the same .
This OLP is the reason I went out and bought a MM Stingray...............the sound with 2 band eq is brilliant for me , I could get on with it, but 3 band lost me . Used to have a Warwick FNA 3 eq band , now sold .
Pete