At $258 the ASUS X99-A is one of the more affordably priced X99 motherboards on the market and The Tech Report thoroughly tested it to see what, if anything, is lacking.  The board still has the "OC Socket" with extra pins which allow the certifiably insane to up their CPU voltage to 1.8V, it retains the M.2 socket, the DDR4 can hit 3000MHz even with all 8 slots populated and three of its six PCIe slots can be used together for SLI or Crossfire.  In fact The Tech Report has a very nice illustration showing how the board works with both 28 lane and 40 lane Haswell-E processors.  Check out the results of their testing right here.

"Rather than loading up on flashy extras and extraneous accessories, Asus' X99-A motherboard focuses on the basics. It has a sensible spec, loads of builder-friendly features, and a diverse array of powerful tweaking options. Read on to see what makes this our favorite Haswell-E motherboard to date."

Here are some more Motherboard articles from around the web:

Motherboards