I have panasonic cameras. I have a G6 and a GM1. I am looking to add a long zoom to my lens collection. It's seems my choices are 75-300 Oly and the 100-300 Pany. I realize that the Pany has ois and my cams do not have ibis. Therefore I am leaning towards Pany. However, it is not out of the question that I may someday get a body with ibis. I plan on using the 300mm for wildlife, birds etc. I don't plan on using it for sports, etc. I also realize putting it in the gm1 will not enhance the portability of the camera. Lol. Please help me with me pros and cons. Also, are there other choices ot there?