Funnily enough both LH and SAO entered dungeons on the same day :P I don't mind the change of pace, it seems interesting. But LH is more interesting at the moment...
log horizon S1 somewhere
Either episode 17 or 18 I would say, definitely no later than that.
If you like Kimi ni todoke, "Say I love you"/"Suke-tte ii na yo" is just like it in a way, I actually like it more than Kimi ni todoke.