I can give you a reason why NOT to switch from PADI to SSI. Just compare their standards manuals to each other, the difference will be obvious! Being associated to both would probably be a better plan. But if you have to choose only one, pick the one with more complete and thorough standards. In the event of an incident, you’re going to face investigators, both law enforcement, dive agency, and private, and lawyers when litigation starts. Every action/decision you made will be scrutinized, and if you don’t have solid and detailed standards to base those actions on, the onus is on YOU! Your liability insurance coverage could be invalidated if you don’t follow those standards.