We had these types of loans early 2000's. I wasn't a huge fan but did originate a few.
UWMHC, United Wholesale Mortgage bought out Portland Mortgage 2004-5 where I was working. Within a year our doors had closed. Mat Ishbia, UWMHC CEO was only 25 at the time.
if long link causes hesitation, try searching" UWM temporary rate buydown."