I get my hands on a lot of avalanche transceivers every year and I’ll echo some of the advice that has already been said here. A lot of the guides/instructors I work with carry the Barryvox S, it’s what I carry as well. There are also a lot that carry BCA T3 or T4s. Some people I’ve worked with think the Mammut requires more patience than the others during bracketing and it does take some practice and understanding to know how it locks onto a target signal and what you need to do if you want to switch targets. With info about what the pros are carrying out of the way I’ll repeat the advice given already, if you’ll learn how to use the advanced features and are not cost-sensitive then the Barryvox S is my favorite, if you won’t learn to use the features and practice with them regularly then the Barryvox (plain) is more budget friendly and is a great beacon.
Ultimately I don’t think search range really changes recovery times greatly since signal acquisition is usually pretty quick. What will change recovery times is how a transceiver handles multiple burial scenarios (flagging/suppressing/changing targets) and clarity when bracketing. This can largely be resolved by learning the transceiver you carry and knowing how it handles these two tasks.
I don’t put much priority on the heart rate/pulse monitor. It doesn’t change the strategy very much in a mixed group. If everyone in the group was wearing them then it might help triage a complex burial scenario but it introduces some tricky moral concerns in a mixed group.