I never said that RAID 5+0 was a common solution either. I did mention that it was used to help improve transfer rates. My point stemmed from RAID 5 not being nearly as uncommon as you think it is. And certainly not as useless. Besides, if you actually read the article you linked to, it's not RAID 5+0, but more like RAID 03. It's not recommended because it's very expensive. RAID 4 isn't recommended because there are other formats (i.e. RAID 5) that are superior to it in every way.
Though we were never discussing what works for you, but the overall usefulness of the RAID 5 architecture. Though if you weren't doing a lot of write transactions, most people would actually recommend RAID 5.