Mcintosh C2600 preamp tube upgrade


I recently added the new McIntosh C2600 tube preamp to my system. It's paired up with the MC452 power amp along with Sonus Faber Elipsa speakers and Transparent interconnects/speaker cable.
I"m looking for some guidance with regard to upgrading the tubes in the C2600. Should I, or shouldn't I ? 
Also, what brand should I look for and where should I buy them. And finally, is this a diy upgrade or should I have it done at a audio shop? 
I appreciate any guidance all you audiophiles can offer
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Mike, one last question. There are 6 tubes, right and left mm, right and left mc along with main input and main output. My only source equipment is a mcd550 CD player, so do I only replace the main input and output? And I assume I would use the gold lion?
Update...I've installed the Gold Lions and right out of the box there was a SIGNIFICANT improvement! To my ears the mid's and base are the most noticeable. 
Hard to believe a little over a hundred bucks could make such a dramatic improvement. 
Looking forward to listening after I hit that 200 hour mark!
I appreciate all who helped.
For my C2300 I used Gold Lions in line stage and Telefunken ribs in phono stage.  I have replaced my phono stage tubes with the Mc brand since I now have an external phono stage.