The 7P55D-E LX is a fine board and the one I'd pick as long as, as you say, you are forever going to stick with singel GFX card.
If you think that one day you might want to add a 2nd two GFX cards, I'd suggest avoiding the 1156 boards from Gigabyte based upon the following THG article:http://www.tomshardware.com/reviews/usb-3.0-performance,2490-2.html
Gigabyte’s P55A-UD4P cuts costs by using the processor’s PCIe 2.0 connections to host its high-bandwidth controllers. Two of the primary graphics card’s 16 PCIe lanes supply its USB 3.0 and SATA 6.0 Gb/s controllers, and Gigabyte disables six more lanes to make the upper slot an effective x8 interface. The USB 3.0 and SATA 6.0 Gb/s controllers revert to the chipset’s 2.5 GT/s lanes whenever two graphics cards are installed, to preserve the x8 transfers each graphics card needs for optimal CrossFire or SLI performance.
Thus, users with a single graphics card must sacrifice half of its peak bandwidth to enable 5.0 Gb transfers to the USB 3.0 and SATA 6.0 Gb/s controllers, while those with two cards must live with 2.5 Gb/s bandwidth limits on USB 3.0 and SATA 6.0 Gb/s controllers. Neither of these sacrifices is huge or even noticeable on most of today’s hardware, yet anyone trying to future-proof their system could be left cold.
Personally, I have been going with the Sabertooth on all recent 1156 builds but it seems today, it's only available in combo deals. http://www.newegg.com/Product/Product.aspx?Item=N82E16813131601