Planning out a panel upgrade that will provide the needed instruments and avionics for IFR training and future IMC missions. With limited space (and limited budget) I probably cannot load up the panel with everything desirable. Will be installing the new Garmin GPS 175 and thinking about a pair of Aerovonics AV30s once they are approved. Questions are: do I need dual VORs? How important is a DME? Thanks for some feedback!