Ultrasonic is good, however it is not magic.
There is a lot of misinformation on them and they are kind of talked about in an almost "magical" way.
Ultrasonic can clean very well but there are many variables that can affect the outcome. I have a 3.5 gallon crest machine that was $1k+ and it can be turned powerful enough to create starburst looking patterns in the alloy, kind of looks like it got electrocuted. That being said I usually use setting 3 out of a possible 10.
One thing it doesn't clean we'll is lacquer. And if tiny passages are blocked with it, there is no contact with the solution, if solution isn't able to penetrate the passage you want cleaned, well it's not really going to work.
Also, ultrasonics can actually take awhile to remove some stubborn greasy, caked on spots. If you are not careful you will remove all the plating from misc parts on the carbs before you remove the gunk. If you have bad lacquer problems the plating is gone long before the lacquer.
If you have a large tank big enough to FIT a whole set of carbs in, it's still probably not going to work well because the tank size is not meant to be directly related to actual volume for normal use. For example I may have a 3.5 gal tank but if I have four bodies it won't work as well as two bodies.
Solution can get very expensive and if they are very dirty expect to change the water a couple times! If you are running a 50/50 solution of simple green hd, that's around $30+ in solution for a cleaning. As the solution becomes dirtier, it is less effective due to the lost energy in all the contaminants.
Our honda carbs are also treated with what looks like an iridescent coating for corrosion protection. If you use a solution that is strong enough to remove really tough grime, expect to lose that coating too. They will come out looking dull.
Basically it can work, and it has it's uses. I still use mine everyday. However they are a supplement to soda blasting. Don't get me wrong I would love it if I could just put a set of carbs in and that advertised cleaning while still assembled and getting into every nook and cranny stuff were true, but it's not.
The best solution is to soda blast, remove residual soda with compressed air, then ultrasonic clean. It will get just about everything when used in tandem.
Do some research. There aren't many videos out there to see, limited pictures, if it were as magic as advertises there would be a lot more out there. Don't get me wrong ultrasonics can work very effectively alone in the right situations, but not as some would leave you to believe.
If you are really curious I can maybe take some pictures for you or maybe make a video later, but just remember it is a tool, not an end all solution with 100% effectiveness. If you expect that and buy an expensive machine you are going to be disappointed.
