Every 77 pouch sits at a single 10.4mg strength. Consequently the choice here is about flavour rather than level. If pouches are new to you, try a milder brand first instead.
Yes. Mix and match any three 77 pouches for £10. Moreover the flavours can be mixed freely, so you are not tied to three of the same tin.
No. They are tobacco free, so they give off no smoke and no vapour. Consequently you can use them where vaping is not allowed, such as on a train or at a desk. The filling is plant fibre with nicotine and flavouring.