I have a GNS530W and a KX155 (no glideslope). The KX155 is a bit scratchy. I am adding a GTN750 and considering my options for COM-2. 1. Sell the 530W and keep the KX155. 2. Sell the 530W and the KX155 and buy a GNC255 + new indicator. 3. Sell the KX155 and keep the 530W to use as COM/NAV-2, plus buy a new indicator. Thoughts?