Here's an advice from someone who's been long in this career. Never go for an editing software that calls slowing down a video or reverse a video "special effects". Trailers are supposed to impress customers, but that trailer just showed me how basic this thing is.
I'm happy with my Adobe Creative Collection. If you want a perpetual license, then go for Wondershare Filmora. Adobe and Wondershare currently offer the best 2 editing apps. I ain't paying a dime for this 2018 basic crap.