Honestly, I have a Modbo 5 (in a SCPH-77004) and a DMS4 Pro (an genuine DMS4 at that, SCPH-39004 w/ Bitfunx SATA modified Network Adapter.)
I much prefer DMS4 Pro... the only thing Modbo5 has above any of its older siblings (4, 760, 750, etc.) is USB boot, but that's it.