It depends on how much I want them to be Friendly with me. In my current game, I gave in to every one of Shaka and Qin's demands because they were my neighbors and had big militaries, while I had only a so so start, for a long time. Now, much later in the game, I have teched way ahead of them, my military outnumbers Qin better than 4 to 1 and Shaka between 2 and 3 to 1. So, I turned them both down for tech "gifts", in lat few turns. If they get p.o.'ed and declare war on me, they'll be toast. So, I'm not too concerned anymore. Since I am going for a space race victory in this game, I won't DOW on them.
BTW, in this game, I'm Ghandi!