Yop this ^
They are both great, the fact that they each cost a point less then what you usually get from their relevant type AND are a 5* tanks which means a 5* stat increase (granted we dont know if this is gonna be like in FKG, where the event girls are toned down, and are weaker than regular gacha girls or not).
I looked at their Elite stats and this is one thing that dumbfounds me.... Arty chan gets 11% HP and only 5% DMG.
M3 gets 13% each.
Went through my other tanks and it seems that the Elite bonus stats are different for each class... Honestly I dont like that.
I thought its gonna be 10% for each, not a variable.
Especially for arty chan just 5% damage boost is not much.
Also the cost of blue prints is extremely high - to get a Elite status you need 3K blueprints, plus other stuff.
Personally I would do elite only after I get bunch of other girls from the Research tab, OR if I really needed that Damage boost in order to clear a extremely hard map/event/PoC lvl, etc. But otherwise I would spend those Blueprints on research.
Though its much easier to get them now, than it was in the early stages of the game. Invasions give you 12+3* tank (maybe 4* with luck) so thats 15 times 5/6.
And yeah Arty chan is very strong boss killer. My lvl15 one with some good emblems can nuke around 80% of the Heavy Tank event boss on node 3 if I manage to get her there alive and with her active ability still intact.
Edna (M3 Satan) is great all around either as a rusher, or if your front line falls and you need something QUICk to fill in the gap to protect your damage dealers in the second row. She can get there quickly, cheaply and if buffed with some emblems can hold on until you either get another Tankier tank up or get enough gears for the defense buff circle ability.