Best Beach Body program for fat loss?

I'm guessing when you say "gain muscle," you mean that you want a more "toned" look? Reducing body fat and gaining muscle (as in adding new muscle) don't really happen at the same time, it's usually a bulk/cut. Recomp is an option, but that takes a long time.

So for what I am guessing you mean, you probably want a program that has a mix of cardio and weights. The best program is the one you're going to stick with, so here are my thoughts on the ones I've done. You can find descriptions of the workouts and some video clips out on the web.

T25: This was my first BB workout. Lots of dance-style moves and coordination, not a lot with weights. I didn't love this program, and it was hard on my knees, but only 25 minutes for the workout. I basically got through it because I was part of an accountability group, and there was lots of stuff to make fun of in the videos. Not one I'd pick up when looking for a workout. Finished the program. Have not tried any of Shaun T's other programs like Insanity or the Asylum workouts, it's all too bouncy and runny-around for an early morning workout.

P90X3: This was probably my favorite of the workouts I did. Mix of strength training, cardio, agility, and flexibility. I felt like I saw the most progress with this and that it improved my functional strength. I also felt like I got a decent amount of rest days. Still want to punch Tony Horton in the mouth for all the bad jokes and time spent talking. I have actually gone back to these workouts from time to time. Finished the program.

ChaLean Extreme: Mostly strength workouts with weights. I didn't finish this program. Chalene does a good job, I just didn't feel like I made a lot of progress. Did this one after P90X3, so I think I may have been a little beyond what I would have gotten from the workouts. I think most of her clocked in at about 40-45 minutes. Never went back to the workouts.

TurboFire: This is pretty much all cardio. Never followed the actual program, but some of the HIIT workouts are favorites of mine, and I have come back to those often for quick cardio.

BodyBeast: This is basically all weights. It's a tough workout, but the workouts are long and the time commitment killed it for me. Plus, I was at a point where I didn't have the dumbbells in the weights I would need to progress with it, nor did I have a bench. It was just the wrong workout for what I had available to me. And I found Sagi to be over-the-top and a tad misogynistic. Never went back to the workouts.

22 Hard Corps: Did not finish, but did many of the workouts. 22 minutes, rotating stations, boot-camp style exercises. I just didn't find it inspiring, my husband is active duty military and the bloom is off the "isn't this type of workout awesome!" rose for me. And again, Tony Horton. Haven't used these again.

Up next (as in tomorrow), Hammer and Chisel: This is the guy from BodyBeast and the lady from 21 Day Fix. He seems less annoying in this video, so perhaps someone had a talk with him. I'm not familiar with Autumn, but from the 2 videos I watched so far I don't hate her. She focuses on the workout and spends her time talking about form, not really socializing with the other people other than to encourage them. From what I've seen, I think I am going to like this. It includes weights, cardio, and functional movement exercises. Not seeing the stretching or yoga I got with P90X3, so that makes me a little sad, but the workouts are short (about 35 minutes give or take), which is good for me.

So from what workouts I have done, I would say if you need a shorter workout, go with P90X3. If you really want to hit the weights, and you have the materials and the time, BodyBeast is a good workout. I've also heard good stuff about Hammer and Chisel, and am obviously giving that a try, so that seems like a good option as well for what you want to do.

Note: I have never followed the diet plans with the workouts. Logging here on MFP worked much better, the Beachboy calorie estimates were always off for me.