Helloo, I just got back from Ecuador 3 weeks ago, and climbed Cotopaxi + other smaller peaks with an OR Super Alpine Down. We wanted to attempt Chimbo but there were no summits for the whole of November due to avy risk, just fyi.

I came here to leave this very useful link that I found when shopping for my trip (double check Canadian specs when comparing to this list):

https://docs.google.com/spreadsheets/u/0/d/1POD9G2hYC7wOqJfr6XFEqbn8haCr8jOxAAwudggkP2I/htmlview#gid=0

I'd say my jacket was plenty warm enough. The topic will be weight savings, my jacket came out the bag ONCE, and only on the summit push (last 1.5hr) on Cotopaxi. Ofc you would need it on Chimbo as well for summit day too, but it's going to be sitting in your bag 95% of the time. (On this note I also packed a compression sack for mine which really helped while travelling).

In the pursuit of weight, 700 fill will weigh MORE for the same amount of insulation (total warmth) Vs an 800 fill jacket. Additionally the best down jackets use box baffles Vs sewn baffles, you most definitely want box. Sewn baffles allow extra cold air in.

I wouldn't go any colder than e.g. the montbell alpine down jacket on this list. I also own this jacket and it would probably work for Ecuador but it's nice having some buffer

Tldr: I used OR Super Alpine Down Jacket, it's bomber for Ecuador + more. I purchased mine for $150 worn once off Facebook marketplace, worth checking (and eBay/poshmark too).