What pole what grip?

[Jungm1420]

I have been training with a college track program and have talked to my coach about this some but wanted to get some more knowledge. We have quite a few poles but since I am a shorter vaulter there is a gap on the poles I normally jump on. Our pole sequence goes from a 14' 155 straight to a UCS 15' 150 flex-22.5. I have went back to 5 lefts and jumped on the 14' 155 easily. I have only jumped on 13'6 and 14' poles from 6 lefts before. From 6 lefts I have jumped on a skypole carbon 14' 170 flex-17.1 holding at the top. From 7 i have jumped on a pacer fx 14'6 165 flex-18.6 holding at like 14' and also a 170 and 175. Coach mentioned today that we do have a 14'6 165. So i am wondering if it would be better to try starting on the 15' 150 holding at 14' from 6, or try the 14'6 165 holding at like 13'9. I know vault poles are best meant to hold right at the top of them so im thinking it would be better to start on the 14'6 165 even though it might be relatively stiffer for the fact that my grip will be closer to the top of it. Any thoughts?