I like Fountains, & obviously love Cigarettes too.
I think the Fountains ride great at high speeds, & have a better hull for going fast under them than the 38 Cigarette does by comparison.
The Cigarette however has a nicer fit & finish throughout the boat for my tastes, & overall I would buy the Cigarette given the choice between the two.
Vee bottoms need to appeal to their owners in ALL areas in my opinion, rather than just in the speed category. You should be comparing the 38 Fountain to the 38 Cigarette, & the 42 Cigarette to the 42 Fountain. That is more apples to apples for comparison.
The 42 Fountain Poker Run Edition is my overall favorite Fountain. The 39 Cigarette Unlimited would likely be my favorite Cigarette overall.