Would you forfeit your capacity to make decisions regarding how you live your life in return for a guaranteed place in Heaven?
The person who posed this question to me suggested that he would have accepted such a trade-off, even in the case that he would be severely impaired, both mentally and physically. There are some beliefs inherent to the proposition, chief of which is that humans have free will, and that those without the capacity to make moral decisions never reach that indeterminate age of accountability.
There is the doctrine of prevenient grace that assumes that one exists in a state of divine grace until they exercise their free will to reject salvation. This doctrine dovetails with the age of accountability standard because children are assumed to exist in this state until they are old enough to make that decision with full moral understanding.
Alternately, since God is all-powerful and all-knowing, doesn't the Calvinist doctrine of predestination, which denies free will entirely, make the most sense? If Someone knows every choice that one could possibly make, how can any decision be freely made? The outcome has already been divinely determined.
It is a divine and transcendent form of determinism that renders immaterial the trade-off proposed above.
In uncertain conclusion, I guess that there may be a one-way ticket to Heaven, depending upon your beliefs, but it is one that I would not accept, if somehow given the choice.