Vibration is "funny stuff"!!! And just as suggested above, it doesn't "just" depend on the machine (good quality or cheapo) but also CAN be changed with:
- A different "bench/table" (i.e.wooden instead of metal, OR vice versa)! ;
- Different machine feet (rubber; carpet; none);
- Bolted down/not bolted down;
- Type of floor the bench/table is standing on, AND/OR the type of feet it has;
- Weighting down the bench/table (e.g. sandbag on a low "shelf").
In short, "it all depends"! The science behind it is VERY complex (and I do NOT pretend to understand it) so, IMHO, the only real way is to keep changing things (from the list above) until you find a solution that's acceptable to you.
Foe example, I have an EXC 21 which are generally reckoned to be one of the best in terms of little/no vibration. It's bolted to a thick ply top which is screwed to a small sheet metal "typists desk", and that in turn is mounted on 4 old-fashion "rubber" castors (you know, the round ball type). On this my machine vibrates "quite a bit" and I guessed those rubber balls were the trouble. So I took them off. Guess what? It got WORSE!
So I put them back on (I need the mobility in my shop). Guess what? It got BETTER than it was originally (and 'onest, the only thing I did was remove - slip off - then replace - slip back on again) those castors! (They just slide into the square tubular steel legs).
I certainly cannot explain that, so as above, I'd suggest just try changing - one thing at a time (and obviously start with the simplest/quickest/cheapest) and stop when you're satisfied.
For you flexible air hose query, one source I do know is Arc Eurotrade, somewhere in/around Leicester. They actually sell them as drip feed lub/coolant feeds for lathes and mills (metalworking) but work very well as stiff but flexible air lines. Google, or I THINK their contact details are still in a sticky in the Metal Working section here.
HTH