After a summer of riding with this jacket, it's time for a follow-up report. The stock windscreen on my ST1300 was replaced with a V Stream which blocks most of the wind even when in the lowest position. Consequently, not much air enters the vents to cool me in hot weather (over 85F) unless I stand on the pegs or hold an arm out in the breeze. The jacket is comfortable in heat except for stop and go traffic. Then it becomes a sauna suit.
With the vents closed, rain has never made it through the outer shell. I've remained completely dry after riding several hours in stormy weather, thanks in part to the new windscreen.
The jacket and liner combo kept me quite warm on a 200 mile trip in 45 F weather and should be good down to 40 F with appropriate under layers. Overall, this jacket was an excellent purchase and can't be expected to handle tropical conditions. I bought it for the waterproof outer shell, my positive experience with a previous Olympia jacket, and I would buy this jacket again.