The bikes seem to be pretty close in spec, with the exception of a full carbon frame for the 7.9, and aluminum/carbon for the 7.7....If you're getting this as an intermediate step to a road bike, I'd go for the 7.7, or even take a step down to a 7.5FX, and save the difference for the roadie......
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2020 Giant Defy 2
Fuji Cross Pro
Scattante 650-R trainer bike
'06 Kona Jake the Snake