I wouldn't give it to the Resto Druids. I would give it to the Hunters on fights that wasn't progress, because if your raiders are high ranked on WoL, it attracts attention. My guild had the top 3 DPS spots on Madness 25 Heroic for a while and we got a lot of attention for it, people literally came to the realm asking about stuff.
DI is good for Survival because of the 3% dot damage that also affects Explosive Shot. Each tick's damage is increased by 3% which is major. Is it better than Shadow Priests and Mages? It depends entirely on their gear, I believe. If the Dark Intent is enough haste for them to gain an additional tick, then it's probably a good idea. Though, these days high end priests tends to gear with DI in mind..
Also, if your resto druids needs 3% haste and 3% HoT healing to stay competitive amongst the other healers, then the druid is doing something wrong. Healers shouldnt have to rely on certain buffs to be able to keep the raid up, healing is a team effort. If it's a fight that's healing intensive or has mechanics where healing is needed, and your DPS seems to be where it should be, then I dont see a issue giving DI to a resto druid.
Just to emphasise my point; Explosive Shot is the main and hardest hitting ability Survival Hunters have. Balance Druids and Shadow Priests hardest hitting ability isn't their DoTs. 3% DoT damage on Explosive Trap and Serpent Sting on AoE can also be very, very powerful.