I jumped on an amazing deal for a Minolta AF 70-210 4.5-6 zoom lens on ebay. I just couldnt pass it up, brand new for like 75% off lol. My question is should I resell this and get something around 100-300. I really wanted the 300m capability. Or is it better to hold onto this 210 and purchase a 300 separately? What I have now is in my sig.