CO2 Honeywell or 2gig

I have a Honeywell 5800co that is at the end of its life. I had no problems with it since it was new. It is 345 and I was looking at the replacements. I also saw 2GIG‐CO8‐345. Never had any experience with that one, are that pretty much the same? Is it one better then the other ?

They are roughly equivalent with the same lifespan of 10 years.

Thank you, do you know the difference between 5800co and 5800coa? Is it coa for Canada ? Can coa be used in us?

Yes, that appears to be for Canada as it is ULC listed. No, use the 5800CO.