Saying 2.5 hose isn't better than 2" hose because of the feel that you have at the wand from the incresed suction causing the wand to be harder to push is like saying there is no difference between 150 ft of hose vs 50 ft of all 2" hose just because it feels like the wand is pulling harder at the carpet......
And as EVERYONE knows the less sections of hose you run, the better your dry times will be and the harder the wand pulls at the carpet.
It's quite a simple concept but I guess some people feel you have to put a scientific number to everything to make it worth buying.
Or just because you can do something cheaper yourself makes it so that it's not worth buying too.
Greenie has always been up front about things. He tells me not to worry too much about 2.5 on my
cds because of the way it's plumbed and how the fast the blower is spinning. Not all TM's are created equal and some have much better results than others. I'd listen to greenie way before I listen to someone who has ties to and listens to someone with mental problems....especially without doing their own tests to prove that what the others are saying is wrong.
Also BTW CFM doesn't indicate how much vacuum you have. CFM multiplies by LIFT. 300 cfm at 15hg is a lot different than 400 cfm at 15hg.
you may get the same CFM at the end of an open hose with 2.5 vs 2. But being at lower lift meaning you have more efficiently transfered your lift to the end of the hose makes a difference. But most don't and also refuse to understand that concept.