Hi! Welcome.
You did happen to notice that the vaporbeast kit is out of stock?
That is a nice setup - if you can wait on it.
Crystal Clear Vaping sells the ePower for $57.50 here:
Crystal Clear Vaping and you can get pretty much any carto you want there too.
The tradeoffs between the two options you are looking at are:
The eGo Twist gives you variable voltage so you can tweak the voltage to suit you carto/clearo and liquids. The down side is once the Twist is depleted you have toss the entire Twist away - the battery is not replaceable.
The ePower is fixed voltage so the only way to adapt anything is to try different resistance devices to change the experience. That isn't as flexible as the Twist. The up side is the internal battery is replaceable and that makes it less expensive long term.