Is it better or does it make a difference if you do your room request via touring plans or on my Disney experience? Does one give you a greater chance to get your request?
Nope. No matter how you make your request, it's just entering information on your reservation record. Whether it's entered manually by a CM when you call, or entered manually by a CM when they read your fax, or populated by the MDE application, it's all going to the same place.
The likelihood of getting your request is determined mainly by a) the number of rooms at that resort that meet your criteria, and b) how many of those rooms are open on your check-in day.