I know this question wasn’t for me but I’ll jump in.
If your panel has a 200 amps breaker in it, you either need a service rated ATS, or you will need to install a separate 200 amp breaker.
The reason for this is that you need to be able to disconnect power in front of your ATS Generac offers both service entrance rated and not service entrance rated.
The ASCO 165 looks like a 2-wire start ATS. Check the enclosure to ensure it’s rated for installation outside if that’s where you plan on installing it (it doesn’t appear to be to me). This ATS may be the more economical option as it doesn’t require Kurt’s more expensive controller (he’ll jump in to correct me if I’m wrong). But you need to include the cost of a seperate breaker and keep in mind it may need to be mounted indoors.
I think the Honeywell is a rebranded generac, but can’t know for sure without a model no.
EDIT-
just for clarity regardless of if your panel has a breaker in it or not you will need to put a breaker in front of your ATS. If you breaker is separate from your panel will reuse that breaker. If your service breaker is apart or your panel you will need to purchase a seperate 200 amp breaker, or buy a service rated ATS, which itself will have a 200 amp (or whatever service you need) breaker for service disconnect.