I bought one of these on special a wee while ago, like you I had the idea of just using it as a one top for everything sort of thing and changing my underlayers to suit the conditions. I don't know if it's that suited to wear on days where it might only shower or not rain too heavy as it's not actually that quiet in the bush, and doesn't pack down at all. In saying that I've still used it as a one top for everything during this winter just because it's nice to not worry about the weather, and because I've bought it now.
It stands up to the weather all good and goes all good in general. I have only used it in the North Island but have been above the bushline in gale+downpour and its warm enough and dry enough with a good hood. Only thing I'd say is it's not that quiet really.
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