Appreciate if someone can share some light on the two lenses I've been offer to buy. Currently I have 28-135mm f/3.5-5.6 and EF-m100/f2.8. Does it makes sense for me to get either 17-85 and/or 50? I want to shoot indoor portrait, newborn, and regular family activities. Occasionally I wish to blow the picture to 16x20 for personal enjoyment. Thank you in advance for all suggestions. Oh, almost forgot, I plan to match these lens with 50D.