Need help to choose Ultrasonic: Amprobe ULD-300 vs Inficon (Javac) Whisper 711-202-G1

[biguso]

Believe that SDT, ctrlsys and others are perfect, but not for my money.
Need to make o choice between Amprobe ULD-300 and Inficon (Javac) Whisper 711-202-G1
The first has wider freq. range (35-45 kHz) as listed in tech data and nice parabola for narrow angle. The second seems to be tough built, easy to hold and i guess has modern schematics.
Do you guys have some experience with that stuff?
Or maybe the third one?

[chemi-cool]

i have the amprobe one for a long time.
Very good instrument, doe's the job I have bought it for.

[RANGER1]

To me has to have very high quality ear muffs that fit over ears blocking out other noises, no matter which brand.
Aeronautical quality.
You could buy a very cheap set & upgrade ear muffs, works the same.

[biguso]

Thank to you guys, made a choice. Read those few reviews about ustrasonics on hvac-talk.com where one guy told not to buy inficon (he conldnt find a leak which was found with amprobe easily). Also there is a bit more information and experience of using amprobe. So I will try this one. The problem why people have difficulties in finding leaks with ultrasonics is as i thing using a device not in a right way. I mean that Operating manual should be read with a lot of attention.
RANGER1 of course. You even can take phones with active noise suppression)

[biguso]

And can you tall me can it hear the leak under the k-flex insulation and how far can it hear in average?

[chemi-cool]

I have used it to locate refrigerant leaks in milk vats, it could hear a small leak behind a 3mm SS sheet.

I did get good headphones and i am sure it made a lot of difference.