Will Numbers handle customized Excel spreadsheets?

I'm trying to get my husband to switch over to a MBP, but he has several customized Excel spreadsheets that he uses every day. I have Numbers on my machine but I don't have any experience using it. Can anybody tell me if those spreadsheets will easily convert to Numbers or will he have to use Excel 2011? If he has to use Excel, is it hard to convert Excel worksheets from a Windows to a Mac?

TIA

The iWork applications, Pages, Keynote, and Numbers will generally be able to read and work with counterparts from MS Office - Word, PP, and Excel. What you may run into, however, are some things which are not compatible such as certain graphics, borders, etc. Excel especially - if the worksheets are custom designed they may not transpose correctly with Numbers.

But since you already have iWork Numbers, why don't you test one of his worksheets to see how it looks and edit. Otherwise, I suggest purchasing MS Office 2011 for the Mac. Applications are the same and file format is the same so there shouldn't be any surprises.

I have MS Office 2010 for Windows and Office 2011 for the Mac and we routinely swap Word and PowerPoint documents back and forth with no glitches. I no longer use Excel but I'm certain it would be the same.

I believe Neo office will even use a lot of the VBA scripting that excel has.