Subliminal Talk

I just bought a pair of earbuds with those specification:

Sound sensitivity: 116dB + 3bd (at 1KHz, 0.5 Vrms)
Frequency: 18-2000Hz
Impedance: 16 Ohm

How well is it for listening to subliminals?

Are you sure the upper frequency is 2000 Hz ? Seems like you forgot one zero I think
If the upper limit is 20000 Hz (20 kHz) and if you listen to masked tracks, I think you will get good results with those earbuds. If listening to the ultrasonic, you should run the speaker test in the free section of the shop. I think the speaker test is also ok to run on earbuds.
If the upper limit is 2000 Hz however, you should ask for a refund for your earbuds because everything will sound like you are outside a club !