Very easy install. They work great! I use them for all my DMD pins. It does darken the DMD a bit. I find it a total non-issue with a color DMD since you can change the brightness settings.

Also, newer Stern DMDs are very bright so I don't mind it darkening it slightly. It might be an issue to some with the lighter orange dots.

Does it affect the viewing from the side or angles?

I can't remember where I got my glare guard but it is awesome. It's the same kind as Comet based on privacy screens. I think I noticed it took a little off the brightness but in all honesty it looked way better. It kinda just softened the brightness just a touch. Highly recommend the product the upper part of your pin goes from like an old CRT to HD.

Anyone have some before and after of the PF glass?

I still prefer this product: http://www.pinballlife.com/index.php?p=product&id=3301

Cheaper, non-intrusive regarding the DMD brightness, none installation needed at all, and it prevents reflection from both the DMD and the BG lights onto the PF....

I think results will be slightly different on each pin. I would just tape a piece of cardboard over the DMD on you pin. Or have someone hold it up and take it away while you stand where you would when playing.

I put one on my ST and it works great. Like said earlier, the Stern dmds are very bright. The glare guard did dim it a bit but like it that way. Here is a pic I posted in the ST forum.

https://images.pinside.com/6/eb/6eb1c0ea5731c877aa8402536cd737c9a12ddfa2/resized/large/6eb1c0ea5731c877aa8402536cd737c9a12ddfa2.jpg

I ordered these and was somewhat skeptical but turned out to be shocked at how well they work. If anyone is on the fence on these don't hesitate to get 'em. Remove the DMD from your game and simply apply with the 2 sided tape on each end and reinstall. They do dim the DMD ever so slightly but I think it actually improves the overall contrast as a result. Amazing results for just $15!