Thank you all for the advice I am ever so grateful for your excellent help, I am slowly but surely getting to grip with it.
I am undecided between the T22 and the Aspire K2, the K2 has a smaller tank, 2 mil and battery 1200 mAH, but it is lighter and less bulky to carry around. The T22 has a 4mil tank and 2000 mAH battery.
I know one can't just give an exact estimate, there are many factors that have to be considered, but as a general rule using a 1.5/1.8 coil:
1 - How many 'moderate' Mouth to Lung cig like puffs you get from a 2 mil tank 70/ 30, 50/50 juice ?
2 - How many similar puffs a 1200 mAH battery can cope with?
Basically I would not want to run out of juice when I am out (or need to refill), or battery power before the end of the day, as mentioned in my first post I smoke 15/18 a day.
Also are the coils ready available and about the same in price for both models?
Cheers Marcus