Kaweco piston filler. Should be good. £135 seems steep. TWSBI Eco piston fillers are great and have similarly reasonable nibs. LAMY AL Stars have a similarly reasonable nib and it's trivial/cheap to fit a converter. Both substantially cheaper. So it's really whether a person wants an aluminium compact piston filler. I want one but I think at that price not so much. If you shop around it's close to LAMY 2000 prices (although a good pen I think it's not necessarily smoother or more functional than a LAMY Safari or AL Star or TWSBI).

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