from what users have mentioned, the performance of the 2400, and in all the printers using the K3 inks, does give a significant advantage over the 2100 and the others using that series of ink when outputing B&W... but the advantage of the 2400 and its siblings in B&W seems to be not very obvious if even visable if compared to the B&W output of a 2100 and ImagePrint or some other RIPs... this is according to, amongst others, Uwe Steinmueller and Juergen Gulbins... the former also has an excellent website on printing as well...
