When I competed, I used a ketogenic diet to get ready for my shows. It worked extremely well for me and that is the only way I would prep for a show if I were to do one.
That said, I find that most people don't respond to ketogenic diets the way that I do because they are using them for a different purpose than what I did.
I would not use a ketogenic diet for general fat loss. It is a very different animal when you are already lean, say 8% like I was, and you are prepping for a show and trying to get down to 4-5%. Keto works really well in that context.
For general fat loss, use a reduced calorie carb based diet and employ a rotational schema for the calories where you follow a 2 days lower calories one day higher calories pattern. Build your diet around 1.5 g to 1.75 g protein per pound of lean body weight. Then add carbs into the mix until you are roughly 500 cals less than your base metabolism. Use that as your starting point for your 2 low days and bump up to base metabolic requirement for your 1 higher calorie day.