Get an Open box mobo?

Hello,

Im looking on newegg and they have this msi open box mobo http://www.newegg.com/Product/Product.aspx?Item=N82E168... Im going to be building an i5 system soon, my first computer Ill have built. The mobo I was looking at was this http://www.newegg.com/Product/Product.aspx?Item=N82E168... I want to buy a gigabyte mobo preferably, but that msi will do well for my purposes. The only brands Im looking at are gigabyte and msi. I have about 120 budgeted for the mobo and some more $ budgeted to use uv cables.

I have a few questions; Is an open box deal like that usually fine as far as the board working does?
And if I get that open box deal what all am I going to need assuming that they only thing that comes with it is the mobo?
Would buying everything that would normally come with it end up costing about as much as buying the board new?

What the system will generally look like: Intel core i5,
psu: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
case: http://www.newegg.com/Product/Product.aspx?Item=N82E168...
hd: two or three Samsung Spinpoint f3s
od
card reader
3 120mm fans
4gig ddr3 ram
radeon 4870 or 4890

Thank you in advance