In my opinion, Sabal Palms had some GREAT features, yet it did feel a bit more dated than Harbor Lake. That being said, we stayed 11 nights there, are going back there for spring break, and I may book two weeks there late August if possible!
It's literally 3 miles to Typhoon Lagoon, so a mile or two further to the Epcot resort area. It was so close! Also just a couple miles the other way is a super
Walmart to stock up on groceries and toiletries (and if you just need some snacks, wine, beer, or toiletries there is also a CVS just one stoplight away once you exit the complex).
The unit was a bit larger than other Marriotts. I requested and received an upper unit (there are only two floors, and I always like to be higher up so I don't hear neighbors upstairs). I don't mind that there are no elevators. We used the gas grills right outside a few times, as it was so convenient.
You can use the newly renovated super pool at the Marriott Orlando World Center, or the little quiet pool right there at Sabal Palms (when we did, we never had anyone else in the pool).
Big differences between Sabal and Royal: Sabal has two beds in the second bedroom, while Royal has one. Sabal has just two floors without elevators, so it feels to me more homey - Royal has more levels and elevators. Sabal is closer to walk over to the World Center. Either way they offer a free shuttle bus. Royal has the large soaking tub in the master bathroom; Sabal has the huge shower. Tip: there is an opening above the shower that allows morning light to shine into the master bedroom, so I stuffed an extra pillow in it and that solved that.
If you're going to the Disney parks, I'd try for Sabal personally! I loved it there.