Need help choosing a baby monitor...which one?

May Mama 330

I am definitely getting the Motorola digital monitor, but which size????? Help me choose! I can save 15 percent today on the 3.5 inch screen at babies r us, but they dont have the 2.8 in stock.

No one has bought it off our registry, so looks like we will need to purchase.

Here's the link to both:

http://www.amazon.com/Motorola-Digital-Video-Monitor-Screen/dp/B004VL2VRO/ref=br_it_dp_o?ie=UTF8&coliid=I2HUKHEGVQ5QY5&colid=1DFPYF10HPGNT