Yes, I have and it's pretty sick. The main use is when the party is fighting something with AOE attacks. DM's I play with usually love to surprise a party with a fireball or a dragon breathing on them in the beginning. Having a tough start to a fight that we need to slog our way to victory seems a common thing, even in the published adventures. So yea, a lot of times the whole party is in bad shape at the same time. Then I pop the channel divinity, heal 5xLevel in HP up to half hp, followed by a Mass Healing Word which for a life cleric heals 1D4 + Ability(4 for my guy) + 5 on everyone, which isn't half bad especially at low levels. Takes a lot of the sting out of those occasional AOE's the party eats. The fact healing word gets a bonus to healing actually makes Life Clerics able to toss out a relatively decent heal as a bonus action and still make an attack, which in my mind makes them better as tanks than any of the other types.
Also it's not a 6th level ability, they can Channel Divinity at 2nd to do it, they just get a second use of it at 6th. Getting 2 of those per short rest makes for a pretty fair amount of extra healing. As I had the Healer feat as well for another free 1D10 + 4 + 1/HD available to all characters and the DM was a bit non-plussed when I started using this combo as he really didn't expect that much ability to eat damage in the party. We rotate DM's in our group and others felt the same way, but it was very noticeable.
Besides, what do Tempest Clerics get that's all that great? The 2D8 lightning damage as a reaction is certainly nice don't get me wrong, and channeling max damage on Lightning or Thunder attacks is some sweet DPS when you need it, but other than that the Life Priest can do just about everything a Tempest cleric can and you're party will likely appreciate being kept on their feet more than anything. But again, it really boils down to what you want to play. If you want to play mini Thor, then by all means rock that thunder hammering cleric to your heart's content because if that's what you want you will not be happy playing a Life cleric. But I did find Life cleric's healing to actually make healing a much bigger factor than usual.
Oh, I have to say one specific example. Had my Life priest in a fight. He had spiritual weapon and Spirit Guardians up. Action was weapon attack/1 action heals/Channel divinity, using bonus action for either Healing Words or the bonus weapon attack, doing AOE damage and hindering enemies with difficult terrain, and used the Channel divinity twice when we were fighting a young green dragon and some minions. Combined all those made what seemed like a terrifying fight into one the DM was kinda disappointed in.