Alright, after trying a 3.5Ω at 5.6v's (8.96watts), a 2.5Ω at 5v's (10watts), and a 1.8Ω at 4.2-.25v's (10watts)
(all were IKV io6's) I can safely say that the 1.8Ω vape at ~4.2-4.25v's is my favorite. Some folks will say that it pointless to use a VV mod for a "lr" atty at a low voltage...BUT my reasoning is this.... These mods will hold the voltage that they are set at til the batt's reach "cut-off" voltages. So, this means I can keep that feeling of a fresh 3.7v battery (4.2ish volts) that is where I have always liked to vape. The 4.2v's-4.25v's with the io6 1.8Ω is my "happy spot". Being able to vape at that set voltage instead of having to swap out a aw imr 18650 every couple of hours to maintain that 4.2v "feeling and flavor" is worth the price of admission any day of the week imho.