I have worked for MHA for 10 years, first as a care assistant, then as senior. I would say your experience completely depends on the management. I am fortunate enough to work with an amazing team.
Management actually care for you and residents. It seems rare with care homes but I can honestly say, employee welfare is high priority. A care home that gets it right. Happy staff = loyal, hard working staff.
Training/Progression.. You are required to do a lot of training, which is ongoing. Daunting at first but it is necessary for the job. You are also encouraged to progress, which is a great feeling. You aren't just a number. They want to see you thrive.
The hardest part of the job, for me, is that, like many health care jobs, you can go home with worries. Did I do this right? Did I forget anything? It's difficult to deal with sometimes.
Overall, I would highly recommend a care assistant job, it is very fulfilling which you can't get with other, similar paid jobs.