I like what WORKS, but I think often the name brand version is just a little better. For me, rotary blades is one of the things I'm very picky about! I tried Harbor Freight blades and they were no good for me. I use Olfa and love them; Amazon sells 5 packs of the 45mm blades for around $15-16. But I did try the other blades and would try others because you just never know until you try something yourself.
Rulers are something I am not brand-picky about. If I see something useful and sturdy I'm likely to buy it - I probably have at least one ruler from every manufacturer by now! I love rulers...