So for the past year (almost), ive been daily driving my FC.
If you've seen my build thread, I think its titled: "My ongoing project car", you know that the 13b I'm running has every single port ported, some of them quite extensively, including bridge-ports on the end-irons.
Basically I'm going to praise this engine here.
But first, yes there are drawbacks.
Bad gas mileage, mine gets 13mpg.
Tricky low end, driving with rpms under 2,500 = just no. Unless your experienced with this sort of thing.

Louder than normal exhaust tone.
Now i don't have much experience with other rotary engines as to compare performance, except an N/A 13b.
But I'm going to say this, there are 2 things:
#1. The noise it makes at idle, just one of the best sounds in automotive history.
#2. When you get on it, and the rpms rocket and go past 5k, the engine sounds like some raging beast right outta hell.
These two things make the whole bridge-port thing Totally worth it.
I swear it puts a big smile on my face, there's a laugh included on there too.