It is the easiest to go across on I-10. Avoid Flagstaff, AZ. I have done this drive. I would suggest, use Hotwire.com and book hotels while you travel. It works well and is easy to use from the road. I would suggest you stay in New Orleans, LA for a night. Or Biloxi, MS for a night. Biloxi is about 9 hours from Tampa. Be safe. Carry wasp Hornet spray for protection. I use the bathroom at Hampton or Holiday Inn, very clean. Avoid gas station bathroom. Stay safe.