Some vacuum manufacturers, and other products as well, have certain target markets and type of consumer they want to go after. If you look at the individual websites of each vacuum brand, you might be able to get clues as to what type of situations, homes and people they are making there vacuums for. (example: luxury home owners, families, budget conscious, college students, etc.) If you look at the Sebo website and demo pictures, you might get the impression that they are targeting people with large homes and/or commercial use, hence the long cords and hoses. I don't think I would put much of a bet that Riccar will make as long of a cord as the Sebo D4, I don't think its intentions are there. Riccar likes to compete with Miele, but their canisters aren't as good as Miele yet. I had a Simplicity Verve for a short time, I did not like it, the canister was very clunky and hard to pull on thick carpets, it was louder, Made in China and the power nozzle very noisy. Tools, except for the dusting brush were small. I believe the Riccar and Simplicity mid and large size canisters suffer from the same things I just mentioned. The uprights are better made in my opinion.
But for cord length- Sebo