Just remember that a silent compressor has a duty cycle of 50% maximum and if you exceed that it won't last long.
That means that if the compressor runs for 2 minutes to fill the tank then it needs to sit for 2 minutes before coming back on again. That is a 50% duty cycle in case you weren't aware of that.
A 1/8 hp is a little small but I guess it would be alright if not used a lot, but even if it does quit then you still have the others you mentioned.
The smallest compressors they use on silent compressors like the ones made by Silentaire are 1/5 hp with a .4 gallon tank for the Super Silent 20A model.
My Jun-Air is 1/2 hp and I built a setup myself with a 5 gallon air tank from a 4x4 store. I put a regulator on it as well as a safety pop-off switch, draincock, pressure switch and tank pressure gauge and it is great.
Just keep an eye on the oil level in the motor and you should be fine.
Isn't it nice to be able to fire it up day or night and not have to bother anyone?
Mike
“Wisdom is the right use of knowledge. To know is not
to be wise. Many men know a great deal, and are all the greater fools
for it. There is no fool so great a fool as a knowing fool. But to know
how to use knowledge is to have wisdom. " Charles Spurgeon