I've been slightly careless, the damage seen in the photo was not caused by cleaning my lenses this time but from knocking my swissflex glasses off a low table onto the floor - a drop of about two foot. The floor is carpeted with a good underlay so the resulting break was disappointing and unexpected.
The optician said they would not replace just the one broken lens now as the spectacles are over two years old and apparently the transition / photo-chromatic coating on the current lenses would not react exactly the same as that of a brand new lens, so I'd have to have both lenses replaced at a cost of around £300.
I will say that after some initial adjustments and slight smoothing along the sharp edges of the plastic stems my swissflex were a very lightweight and comfortable eye-wear choice. Looks wise these specs are second to none but the one thing I didn't like about swissflex is their fragility and ultimately that became the deciding factor when it came to replacing them or just the lenses. I've now replaced my swissflex rimless frames with Titanium full frames because to me substance is more important than style.
I will say that after some initial adjustments and slight smoothing along the sharp edges of the plastic stems my swissflex were a very lightweight and comfortable eye-wear choice. Looks wise these specs are second to none but the one thing I didn't like about swissflex is their fragility and ultimately that became the deciding factor when it came to replacing them or just the lenses. I've now replaced my swissflex rimless frames with Titanium full frames because to me substance is more important than style.