I could not find any info on the puffer jacket, but the hooded micro puff jacket uses 2.7oz insulation, that is about 77 grams, so the insulation is simmilar weight to the 80g insulaton in the montbell parka.
The only real difference the patagonia jacket has is durability, but the warmth I think would be about the same
The micro puff uses 1.3oz 20 denier fabric with DWR
and the mont bell uses 15 denier balistic air light with DWR
You would save weight with the mont bell, but sacrifice some durability, it depends what you will be using the jacket for I guess
But in all my experiences with the balistic airlight fabric, it has proved to be durable enough for me.