aerodynamically, not much gain. But if she is smaller and struggles with handling in gusty winds, the Firecrest rim shape is quite noticeable in terms of stability on the deeper wheelsets. Having spent a lot of time on all of them, the 808 firecrest handles like an old 404 aluminum.
There's not much speed gain, unless you want to go with really wide tires (which it doesn't sound like is an issue for you), but the stability difference *CAN BE* meaningful, especially for women, who are quite often smaller/lighter.
And, certainly, upgrading a rear 808 to a disc can be a meaningful upgrade, though it varies by bike (to a certain extent).
But the wheels you've got are great. I put a ton of miles on those wheels in training and racing quite happily.
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