The one good thing about Cabana Bay is that you can walk right across the street to SF and ride the boat. If budget is the issue which for me it usually is.
When it comes to HHN, do they let you take the boat to SF (or RP) if staying at CBBR?
I know they check keys to get to the boat dock late at night, I imagine they start check around 11 or 12, not really sure what time they close the boats to non hotel guest and I know CBBR keys are different. I assume they do not care as you are a hotel guest, just wondering if anyone has done it.
I love CBBR and don't mind the walk, but we did take bus when we went to HHN...heck, last year we stayed at SF for HHN and walked to the park as lightning closed the water taxis each night when we decided to head to the parks.
Anyway, I swear walking to the bus feels like it is as far as just walking to RP anyway.
Anyway, to the OP, I think you can get by w/o Express in Sept. I have enjoyed my stays at all of the on site hotels thus far and I like them all equally but for different reasons.
If you have a car, parking is cheaper at CBBR, so that helps as well (not by a lot, but if you are there for a few nights it starts to add up.