I just bought my second Six Moons Design tent and decided to splurge for the more compact and less heavy 45" carbon fiber pole pack. Because I have the aluminum poles for my first tent, I can easily compare the aluminum and carbon fiber options as well as the 3-section vs 5-section pole design. Functionally both the aluminum and carbon fiber poles do the job of holding up the tent. It will come as no surprise that one big advantage of having a 5-section pole, verses a longer 3-section, is that you can more easily pack and fit your tent into a pack/bag without worrying about the poles being too long. The weight savings with the carbon fiber option is also a bonus. I use my Six Moons Design tents for both backpacking and for bicycle touring. The lighter and shorter footprint of the 5-section carbon fiber pole is also advantageous for fitting the packed tent in my panniers (it is that small). My guess is you are probably interested in Six Moons Designs for the ultra light qualities of their gear. If that is the case there is really no other option than buying the carbon fiber poles for your next adventure.
Remember, buying aluminum poles for an ultra light tent would be the same as making Usain Bolt run the 100 meter dash in hiking boots. Performance may suffer!