Is this feasible? I wanted to sign up my parents with the unltd tnt 15gb for 2 lines and use some of the eBay refills, but not sure if the refill from eBay worth of $35 credit for example is actually allowed for shared lines ( If I buy two of these, their account will have $70 balance and $57.50 will be deducted monthly. That trasnalets to them paying only $42 and change monthly. Any info would be great.

I'll be asking this seller as well after i post and will update