Quick question. Curious about which to get. Read a lot about here but nothing with my exact measurements, although I have seen a few people with 6.5 girth who asked which to get. I have 5.8 in girth and 6.5 in length. I know I can fit in the X-40, but would the X-40 be a better choice at this point? I just got an extender a month ago and plan to use both around 5 times a week.