They are both around 150, but there are probably 15% off Petco coupons that can bring the price down even more.
The advantages I see of the Seaclear are supposed better clarity, weighs less, and you can get it clear, or with a blue or black back. However, the top isnt open, and there are only a few slots to put stuff in, which means you can't put a light on top with the 4 legs that attach to the edges of the tank.
For the ADA, obviously since there is no top, you can put a light on there with 4 legs and it will be okay. You also don't have to worry about fitting anything in the small slots on the top of the Seaclear. Are there any glass frameless tanks like the ADA that are cheaper?
another thing to think about with the acrylic tank, if you are not going to put a canopy over it the top works like fiber optics, if your light is near the edge of the opening in the top when you look at it from the front the top looks like a light shining out at you, very annoying.