I believe the Del Sol and the Desert Inn are owned by the same people. The breakfasts are very similar - pastries, fruit (red delicious apples or oranges - the Del Sol seems to always have both, while the Desert Inn has one or the other), cereal (a cheerios and a corn flakes - probably generic), bread/toast, OJ, milk, undrinkable coffee. I know the Desert Inn usually has raspberry lemonade and the Del Sol usually has muffins (but I'm not sure if both have both). I know the Del Sol (only) has toaster waffles. Both have the usual fixin's (butter, jelly, non-dairy creamer, sugar, Sweet & Low) to go with the items.
The Del Sol area seems smaller than the Desert Inn area and they don't provid trays to take food back to your room like they do at the Desert Inn.
The rooms at both are fine, nothing special. The walk to the park from both is awesome!