It is the same solution Asus put on their P55 motherboards. The Marvell 6 Gb/s chip isn't as fast as new Intel 6Gb/s, but then again you can't get the Intel on a card, and Marvell is the only other game in town. It also (by consensus of investigations by people) doesn't support TRIM. However most SSD garbage collection is quite adequate for most users. I haven't seen a drop in performance in a months of use.
I am satisfied with the Marvell on my Asus motherboard. I get sequential reads of 350 MB/s (max you can get with SATA 3 Gb/s is 260 MB/s) and it is quite stable with either the Marvell or Microsoft AHCI drivers.
I don't think Asus is producing the card anymore, but here are newegg reviews:
It is also unavailable at Amazon. Don't know if it could even be had.