I recently purchased the new Baader Flip Mirror II diagonal. So far, I love using this diagonal. It makes my planetary photography much easier since the field of view with my ASI224MC camera when attached to a Televue 2.5x Powermate is small, and it can be hard to get a planet in the field of view of the camera. Now, I can get the planet centered using an eyepiece, flip a knob, and the planet is right in the middle of the camera field of view. No more wasting time trying to find Jupiter or Saturn with the camera and computer screen.
The quality of the diagonal is great, and a simple knob allows you to flip between using the top port on the diagonal and the rear port. I haven't compared this diagonal with my Baader prism diagonals enough to say how they compare visually, but this isn't really a diagonal you would buy just for visual use anyway. The main reason to buy this is for convenience to allow you to use multiple pieces of equipment without having to swap them out. The main downside is the expense. The diagonal itself costs $227, but you will need to buy adapters to hook up all of your equipment. For my setup, the total cost was $446. So, if the cost is not an issue, this is a great setup to have.
You can watch a video review of the diagonal below.
Baader Flip Mirror: https://agenaastro.com/baader-flipmirror-ii-star-diagonal-2458055.html Baader 1.25" Clicklock Adapter: https://amzn.to/3eJ1uto
Baader 1.25" Helical Focuser: https://amzn.to/2zT2AUx
Baader SCT Adapter: https://amzn.to/2ZZxCVm
Some of the above links are Amazon Affiliate links. As an Amazon affiliate, I receive a small commission on purchases made through those links.