10A @ 5V is a lot of current for one wireon either side 12 or 5. Personally I would use several smaller 2 or 3 amp converters like one of these for $1.59 ea: From Chip Partners on Ebay.
http://www.ebay.com/itm/1pcs-DC-DC-Buck-Converter-Step-Down-Module-LM2596-Power-Supply-Output-1-23V-30V-/251066005460?_trksid=p2045573.m2102&_trkparms=aid%3D555001%26algo%3DPW.CURRENT%26ao%3D1%26asc%3D34%26meid%3D2232964115197841127%26pid%3D100034%26prg%3D1030%26rk%3D1%26sd%3D170880554877%26
The LM2596 is good to 2 A and your best shot for a reasonable and affordable power supply. It is a "reference" design recommended by National Semiconductor for their part and well tested. I did find several 10 to 20 A switchers but they were in the 15 - 20 dollar range.
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