Apple Logic Pro /LogicExpress Discussion

This is a really naive question, but in all my years of using Logic,  
I've never recorded a band with guitar players who wanted to plug  
directly into my interface.  But I am now, and have more guitars (4)  
than Hi-Z inputs (2) on my Firepod.  SO here are my questions:

1.  Does MOTUs original 828 MK I  have Hi-Z inputs?  I know the front  
ins on later versions are, but I can't find anything about that  
feature for my unit.

2.  Is there any way to record a guitar through a Lo-Z input short of  
buying a DI box?  Why is it bad?

3. Also, if I do end up using both my 828 and FP-10, is there any  
drawback to creating an aggregate device?  Does that take more  
processing power or reduce quality in any way?

Thanks for any help anyone can provide.

Gregory