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I've never heard of Koo but those frames look nice and if you can get them cheap with inserts they could be well worth a try. I've never used inserts but i assume they're clear prescription glass inside a regular lense which i doubt is quite as good as a proper lenses as well as being heavier. How did @cornelius_blackfoot find inserts in use ?
I've used my regular glasses underneath/behind my Aerohead visor once and i got wierd flickers of glare between the two lenses and whilst the visor cleared fog ok my glasses didn't which i didn't like but maybe that was the two lenses were a bit far apart from each other or at 2 different angles or something which hopefully shouldn't occur with clip ins. My prescription is only - 2.0 left and - 0.75 right eye and first time wearing the Bolle's out on the bike was a a real wow moment for me.
I've just got some brand new Bolle sixth sense with gold to green mirror photochromic prescription lenses not inserts and they are great i really don't know why i waited this long either going without or faffing about with contacts and any day now I'm picking up some Oakley Trajectorys in clear to purple photochromic. Really expensive though and i don't think you can get Sutros with prescription lenses i think the only Oakley shield lenses for prescription are the Radar ev path. Same as Adroit says just go dark with driving glasses as the lense treatment to make them react behind glass makes them take longer to react and the mirrored Oakleys don't go fully clear so i went clear to purple for dark to medium conditions and sunny to bright sunny conditions are covered by the Bolle's. Bolle's we're £400 with loads of frame lense colour and shape options the Oakley were £500 with less prescription options. Pretty sure Bolle do the chronoshield in prescription lenses which may be the closest you can get to the Sutros if you like large shades. Also on shield type lenses Oakley and Bolle put the prescription lenses in with a cut out which you can see and it isn't flush. They have to do it this way because the prescription thickens the lense and if you do that to the whole lense with a shield it would require a custom frame. When they go dark you see the insert less and with mirrored finishes even less but they still don't look as good as regular shades so with glasses the have regular fit lenses like the Trajectorys they look just like regular sunglasses.