Wanted: opinions for US2 Graph

Would like to hear some recommendations for a graph utilizing the US2 on my new Ulterra. I am running an HB 899 at the helm and would like something that will network and take advantage of Autochart. (next on my wish list). I wouldn't be opposed to a 2nd 899 but really won't need the SI/DI only the 2D. Also not really wanting to spend that much even for a used unit. Trying to stay around $3-400. Not opposed to used as long as its in my budget. Any opinions would be appreciated.