75C is Buck/Boost of course. Evolv only builds the best possible. I feel 250C hits harder at same temp/watts and fires/heats faster? My imagination or this is true? It might be my imagination since 75 is smaller than 250 Duh. Not sure. Anyone else notice this? Either one is great. 75C with 26650 makes nice little shirt pocket Mod. I also notice with 4200MAH 26650, 75C lasts about 1/2 hour longer? Maybe a tradeoff? I only use 34 Watts anyways. Just not sure if this is noticeable to anyone else? Sorry for serial threads today!