yes back ups are a must... the initial cost might be higher than what your smoking budged was (even if you dont get shinytitis which is very easy to do) but once you can find the hardware you happy with and backups for it (a must!) the cost can even itself out...
myself however found that also what i want from vaping keeps changing and i got into pretties.. so I kinda gave up on the vaping is cheaper than smoking .. it has turned more into a hobby than a cost effective smoking cessation... great thing is you can go either way and the clouds will still rock
safe travels in vapeland