Digital BW, The Print

Hello 

I've recently purchased a new Epson 7600. I plan to use the UT7 ink
set. I have two 
questions:

1 - Do I need to use the MIS Cleaning Cartridges, even though I have
NOT used the Epson 
UC inks?

2 - Will the use of 3rd party ink sets void the Epson warranty?

Thanks in advance for any responses.

Brian.
Brooklyn, USA

PS: I got a great deal on the Epson 7600 from Logix.com.