RE: Another question from the beginner
If they were the same everyone would be shootin 50's. Some things to consider. A 50 is slower than a 70 (depends on setup). So there is more time for things to go wrong with the 50 before they hit the same spot. I think there would be alot of time at 30yrds. Also a 50 would require more pins to get you to 30yrds. meaning more mistakes possible (I use one pin to 30).
Alot of people are very successful with 50's. It's your skill that counts and a good bow set up right, 50 or 70. If you ever think about going after something bigger the 50 won't due.