i own flex and i3 pros, and used to own bog standard i3s, i didnt like bog standard i3s, too heavy and felt weird, then bought some proflex, which are very nice, no troubles with steaming up unless you get water in the lense, and i have recently bought some i3 pros, which i prefer over the flex, nice and light and very comfy and havnt fogged up on me yet, even when training on the hottest day of the year. in the end these threads are pointless, you need to go out and try them on and find out for yourself
(if you decide to go with flexs, i have a nice set for sale for a decent price
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