It barely penetrates the wood, enough to seal it real good. If you want the finish to really penetrate you will have to use a vacuum or pressure tank to get real deep penetration. The cost and time factor adds up real quick, a basic cheap tank with gauges etc will run about $100, cheap air compressor another $100, and miscellaneous another $100. But plan on doubling those figures to a total of about $500. Then the time factor. I can get total saturation with my rig in about 24 hours, probably about 3 hours of my actual time involved, and then it takes 2 weeks or longer for the finish to totally cure.
These are not calls that John Doe will pay the extra money for. You have to have extra special customers that have the extra dollars and willing to part with them. I do very few calls like this, when I get the wild urge and they are finished I send out emails to the people I think might be interested.
Marvin