Started with 2 protank 1's - broke threads off base of one (dropped on carpet - Vamo)
bought a Protank 2 (was going to just order a base but it was out of stock, everywhere) - gurgles and floods constantly no matter what head and even with 6 2mm flavor wicks (could barely get the stem to go back on)
found someone here with 1 NIB protank 1, 2 slightly used protank 1, and 1 slightly used mini protank 2 (1st version with fixed drip tip) for $7.50 each
found another website with NIB protank 1's on clearance for $10 bought 2 (what was left in stock)
took base from new Protank 2 and put on my original protank 1
Have no desire to throw money at Protank 3 due to coils are not compatible with previous versions
So I guess you could say I prefer the Protank 1
One little thing I learned, rebuilding heads for my pt1 and 2. They will leak/flood/gurgle unless you have almost exactly the right amount of wick material for your juice concentration. Both having too much and too little can give you these issues.