QUOTE(decondelite @ Nov 19 2017, 11:22)

No, he hasn't got enough HP bonus for fullcure and elixirs to be really useful. A regular cure or a health potion are way enough. Fullcure and elixirs are for HP walls with a full Leg set, full HP tank upgrades and a few Jug 5. They're starting to be useful around Lvl300, and even right now I still don't have enough HP to have more than double the effect of regular cure/potion.
At 150, HP Tank gives +70% bonus HP (+80% at 200). A multiplier of 1.7 is notably better than a multiplier of 1,
especially right after a Spark, which is when you really really want to get as much HP back on the next turn as possible. Sure, someone higher level or with IW'd gears could have a multiplier of 2.3 or something, but that's no reason at all for a lower level player to avoid the option of more health restoration. Even if it's not as efficient as it will be 100+ levels down the line, Fullcure/elixir is still a pretty good option to consider. Mana conservation isn't really important enough to be a consideration (this can be proven pretty easily with Income Summary), and especially if a player doesn't have Spark on IA and wants to re-cast it, they'll do well to err on the side of caution before it's cast and they're safe, rather than risking it just to save a measly bit of credits worth of mana.
Sure, if someone's only on Hard or there's only one monster left with no SP or something, one might cast Cure and have Regen chip in over the next few turns until it's dead, but that shouldn't be the only option to consider, especially if a player is in a battle series where they're feeling like they're taking too much damage (which is what this situation sounds like).
(that's assuming a player doesn't have any HP bonus from armor prof, which they probably will - making Fullcure even more useful)