Joe,
Welcome to the forum!
Cherokee Purple does great here in PNW. Gold Medal and KBX are very late in our climate.
If you like to try a bi-colored tomato, I'd recommend Northern Lights (
http://tatianastomatobase.com/wiki/Northern_Lights ), it is not as late as other bi-color varieties.
The DTM dates vary quite a bit from year to year, and highly depend on climate. What can be 75 days for Texas, can be 85-100 days for us in PNW, depending on the year.
Tatiana