You'd have to weigh in the cost of the procedure and the cost of the reversal when he's old enough to know that he wants kids. If he never wants kids, then that'll be something he has to explain to any girl he dates. Maybe they'll be ok with adoption.
Aye, it is reversible to a degree, especially if you have your sperm frozen.
As far as costs go, if I remember correctly, it is relatively common for it to be covered by medical insurance, giving a very modest co-pay in the end.
I think the only complicated part would be telling your dates. But alas, that's something to discuss when things are working out well and have steadily progressed within the relationship. For harmless casual relationships, it's better to keep on the down low.