I also purchased the ZY blades from Stern and absolutely love them! The artwork is top notch and it blends in quite seamlessly with the rest of the game. One of the aspects that I like about it in terms of design is that the buildings are different scales and at different distances so it gives the sides a lot more depth than other blade art out there. There are also nice details like trees in the foreground around the library on the left and New York harbor (with the Titanic ghost ship from GBII) on the right. This helps break up the repetition of the buildings and makes it feel more like a city.
Getting them installed isn't bad if you remove (or lift up and turn) the playfield. Definitely a 2 person job! I didn't have any Rapid Tack so I just applied soapy water with a spray bottle to the back side of the decals in order to have a little play in lining them up properly. Worked out great! As mentioned above, you will definitely want to squeegee the water out from behind the decals once you have them in place (I actually just used a credit card). Hold a towel at the bottom as you move along the panel to catch the water that comes out. Even if you get a bubble or a ripple, you'll be able to flatten it out by working the squeegee downwards or to either end of the decal. I got a ripple on one of them during the install and was able to just work the ripple down to the back end of the decal to smooth it out.
Sorry for the mediocre pics but you get the idea.