>>76693381
>>76693372
2025 Contend 1, brand new, $1,000
https://www.giant-bicycles.com/jp/contend-1
9.5kg
aluminum frame, carbon forks
Sora 2x9

2025 Contend AR4, brand new, $1,000
https://www.giant-bicycles.com/jp/contend-ar-4
10.3kg
aluminum frame, carbon forks
Claris 2x9

2013 Defy3, used from a large reputable bike shop, $600
https://jp.mercari.com/shops/product/9XTc4sqqsJx5t9UAsUK8cG
9.1kg
aluminum frame, carbon forks
Ultegra 6800 2x11

The 2013 is 40% cheaper, but obviously is a very old bike.
I will be entirely just using this bike for cardio, so from that perspective if the 2013 bike which is much cheaper works just as well then I guess it's the better option?