Yes, vittatus do well in a group like all phyllobates. Mine are pretty bold, but not as bold as lets say D. azureus or P. terribilis. These frogs call constantly and are definatly one of my favorite. They are a smaller Phyllobates frog. Get them!
I have a 2.1 and mine are somewhat but I get top see alot of them. My males seems shyer then the female is.Ben Green and I were chatting and he said his are very boldGo to http://www.thechochut.com. Ben has some of their different calls and their meanings there. They are well worth seeking out.