I was very proud of never having felt the need of a noise supressor. But when I switched from playing guitar in a bass amp with a distortion pedal (EHx Metal Muff) to using a real guitar amp with its built in distortion... my Needs changed.
The amp (Peavey Bandit) isn't noisy, at least with my settings, but I like to use flanger in front of the amp and my Neo Mistress, when was turned on and I wasn't playing, made a lot of noise, I guess it did before but, since my bass amp lacked in the mid range when compared to the Bandit, I never noticed that much. So I had to swallow my pride and search for a noise supressor.
I knew about the Boss one, since my old PW10 Wah had some NS2 inspired noise gate functionality in its drive selection mode, but I never liked that implementation on the PW10. So I did what I usually do when in need of a new type of pedal: see if EHx has one, and they did! And, as usually, it is cheaper and with all the essentials.
It took a while for setting it up correctly, I read about the X method (using the amp in the Noise Gate's FX loop), I tried what I read online but I figured that my problem wasn't the same as most people had. Usually the problem reported is that the amp is noisy, mine isn't, so I tried to isolate the noisy pedal.
The best placement I found for the Silencer is right before the amp, I have Wah -> Compressor -> Phaser -> Flanger -> Soft OverDrive -> Silencer, than a volume pedal (mostly to soften the amp's distortion in some parts and to volume swells) and then the Bandit. If I turn the Silencer off I hear the Mistress and the Compressor, but with it turned on they stay silent.
I tried the Silencer in the FX loop but I couldn't find the right threshold, since what worked to the distorted signal was too much for the clean signal. So I ended with this solution, I cut the noise the clean signal path and then I apply distortion, it works for me! And I can still play around with letting notes ring for a long time and generating feedback with distortion and flanger.
The Silencer is a great tool, with a FX loop its versatility is on pair with the more advanced and expensive Noise Gates I think. I really find it useful, competent and makes me sound more professional without unwanted extra noises.