My sister lives in ft. Myers which is about 45 min/hour north of marco.
In 2013, we drove from CT. We just did 95-I 4- 75.
When we drove home we lefts day earlier then we planned, well in the afternoon because I said ok only if we went to Dtd. We figured what the heck, we had time we'd try the inland rt 17. There was no traffic and I saw my first tin roof ever!
In 2014, we took the auto train. We bypassed that rt 17 exit and stuck with 75 both ways.
When my sister drove up to disney in 2013 to meet us there (this was another trip) she took 75.
I didn't always feel safe on 17, I am sure it was all fine and dandy though but one of the bathroom stops (kids couldn't wait any longer) I swear turned into a nudie bar at night-it was a gas station.
I think 17 was shorter in miles or time and 75 was shorter in the opposite.