I generally don't care for reading about a kiddie all growed up. That did affect my impression a bit. Also, not being really in the mood.
OTOH, it was pretty decent there - H is the master of mechanical stuff, h shares similar interest. Heroine has past, H helps her beat it. More impressive though was the family that conveniently appeared when needed, and stayed away when not (don't like familial interference).
Thought the whole thing with H having his heart stop not once but twice was a bit much though. Makes me picture him as a delicate flower. Eh, sure you want me to do that?