Natural gut is better than all multis but I agree Tecnifibre multi's are closest. 1. NRG2 17G - my favorite multi 2. X1 Biphase 16G - excellent multi but it notches faster than NRG2 in poly hybrid 3. MultiFeel - if you can still find it. Very good feel but durability not as good as NRG2 TF strings also rate very high in retaining tension. I know some complain about x1 bp losing tension but NRG2 is excellent at retaining tension. Some mentioned LaSerFibre SNGP above and it is a great multi and gut like, but LaSerFibre is a big rip-off company and it is near impossible to buy their strings.