Academy is an initial stage venture where you join in the early phase of your startup, however accelerators should be joined when the product is ready. Accelerators can speed up your business.
I've been part of the SUH Academy for two years now. I've not been part of other academies I'm not sure how it directly compares. Several elements of SUH were the national presence, ability to network with healthcare insurers/providers/technology companies and the regular organized support opportunities. The staff is very experienced and knowledgeable of the health start-up space. There is a time comment, and you need to be willing to put in the time daily to get anything out of it. They are not going to run your company or set the vision. They will give you the tools and connections to become successful, but you need to put in the time.
Startup Health is one of the best healthcare accelerators in the USA. I have personally attended several conferences, meetups, and have had the opportunity of mentoring and advicing some of the startups.
Some of them have now gone above and beyond to raise millions of dollars in funding and offering their products/services for our community.