The Fit is only a USB2 drive, so Readyboost would not give you any major speed increases. Most spinning disk drives have faster write speeds than the USB2 limit. Additionally, the Fit almost certainly uses TLC NAND. TLC has inherently poor write speeds and a relatively short servie life that would be further accelerated by ReadyBoost.
The small capacity of this drive further limits its usefulness, plus small sized SSDs have gotten so affordable that the price to get the insane speed benefits of a SSD isn’t a whole lot more than the small gains with ReadyBoost.
