I am into the so called 'Old school sound'. Before I spend the ££'s / $$'s on a set of strings your advice welcome. I am a jazzer. I am looking for a medium tension set that is good for both pizz and arco. Steel or synthetic that hold their tuning. I like the 'Innovation' sets--tried a couple of theirs--like the sound but find not to good for arco. I have tried Evah Pirazzi Weighs, my favourite so far for both arco and pizz. What have you tried and liked? Do you 'mix and match' strings? If so what makes? If you 'mixed and matched' steel and synthetic would you get an imbalance of tone and volume? Question's regarding gut strings (Never tried): Good for both pizz and arco? Hold their tuning? Long lasting ? 'shelf' life? Would you buy a used set of gut? Look forward to your experiences on string types. Many thanks.