I like that you can use this with your own custom protocols or even just simple TCP/IP connections without too much trouble - if there's something in particular not working properly then they will probably fix those issues quickly! It also has some really cool visualization tools built into its interface so seeing what happens when different attacks are performed makes things easier than trying them out yourself via wireshark / tcpdump etc.. The only thing i dislike about neossii was how slow their website loads sometimes but other parts work well enough for me personally.