Either one is far better than a tooth brush for sure. Each has it
pros and cons so pick what set of characteristics best suits the way
you work and what you are working on
Steam...Fast, deep penetration behind impacted stones, one step
process usually Sonic...dunk it and go do something else, cleans
multiple items at one time. Not as hot so sensitive materials may be
safer, generally cost much less to step into, like around $200 for a
small one. Get a heated one or else there's little point.
Steam...pricey, decent units start at $500 or so. Noisey. Require
periodic maintenance, some require distilled water. Potential safety
hazard, some limitations on where one may be legal to operate. You do
one item at a time. Tends to dislodge loose stones with a vengence.
Warmup time required is longer than a sonic. With heavy use you may
have to wait for pressure to regenerate. Sonic...slower and not as
thorough. Requires continueing purchase of cleaning solutions( the
better ones can smell). Will not remove really hard packed crud.
Ideally have both. If only one unit is feasable I'd suggest the
sonic. Step up to the steam when its necessary. Depends on what one's
budget is though. Whichever way its always advisable to get the best
unit you can afford.
Ah! I'm late for work again.