How are you getting there?
I have been to disney-usually thanksgiving week or first week of december. We always drive. our first few times we were onsite Port orleans...but then one year someone offered us thier timeshare right outside of downtown disney.
Honestly, the only thing missing from the off site experience was towel animals and Mickey soaps! LOL
Another important consideration is if you are not a resprt guest you can't do the dining plan, or extra magic hours if those things interest you.
Granted you can go real cheap with a regular hotel, but with the time share, we were able to get a condo with 3 bedrooms, a kitchen and our own laundry...VERY cool, to eat breakfast every morning in your room. And do laundry....I guess you can find very good deals on these online....
As far as transportation goes...it was quick 5 minutes to the parks...I don't remember much issue with parking at all, yes you pay to park, but small price for what I felt was actually a convenience.....and there was no waiting for the crowded bus to show up either...We used the bus once or twice when we couldn't monorail...and honestly I am glad we bring our car! Its very convenient.
Definitely a personal preference.