Not a bad approach, I have used it for years when I thought it would benefit the customer.
However some customers still would like to have the system as an "all in one". We have had some problems with "cycling issues" with the "32" and the "24". Most of my customers have learned to live with this and are happy with what they purchased.
Toshibas version of e-cabinet
I have no experience with the Toshiba 3511.
Have you tried pricing the NEW 2228 (Ricoh), keep in mind this is the same engine as the 38 and can produce outstanding volume. Black & White copy speed is 7 pages slower however the color speed is 10ppm higher.
Wish I could help with some more info. Please make sure you uncover all of the customers needs. Do they need color scanning, color scan2email, any one of these could deal a knock out blow to your idea.
Also a quick run through of the Toshiba PCL6 print driver leaves alot to be desired with "ease of use" . Make sure you show the customer the RPCS driver and explain the advantage to the customer for using this driver.