I have been using a primus with the piezo for at least 10 years now. I can shave 1 oz off by going to the snow peak, but the primus heats so fast its silly and ignites with the push of a button. a small iso can, the stove and a couple oatmeals fit inside my .5 litre stainless pot snugly. I spent 50 bux on a ti pot that is only a couple grams lighter then my 20yo stainless one, but it is not as good a design, it takes longer to boil. my little setup will smoke my pards jet boil by a good bit, and takes up less then half the size.
IMO go piezo what ever you do. if you plan on cooking anything but water, look for the biggest most controlable burner you can get. little burners with big holes make a lot of concentrated heat.