360 vs. 340 vs. 318

Does a 340 stroker kit do anything bad to your engine? Does it become less reliable, or shorten its life, or make anything wear faster? Does it cause other things to break faster or anything like that?

I have a good 340 core and I'm addicted to power. I've been slowly gathering parts and figuring out what I want to do. Maybe a stroker is it? I want a reliable car though.