The property itself (with the Timeshare units) is pretty nice, and the proximity to the parks with it's location can't be beat.
HOWEVER....
The Wyndham Grand has a few "hidden charges" that they will hit you with on top of the nightly rate you are being quoted. There is a daily "Resort Fee", as well as a daily self-parking fee (or more if you want Valet). Together they'll add around $25/day or so to your rate.
It's honestly often a better deal to look into renting a unit from an owner on the timeshare side of the resort. Often you can get a full 2bdrm condo for around $100-120/night which includes free parking and access to all the resort amenaties. There are a few tradeoffs (such as daily maid service), but the extra space, washer/dryer in the room, and kitchen which you can use for breakfasts or to reheat leftovers from your TS meals I personally tend to feel really helps more than make-up for it.
As for if it's possible to have "the magic" staying offsite.... Honestly, it's a matter of opinion. Personally, I love staying offsite at a nicer and larger place than I can find onsite on my budget. My few times staying onsite, i just haven't experienced anything more 'magical' at the resort that justifies the extra $$. I also have seen posts from people here who have tried offsite and will happily go back to cramming 4 people into a Value room instead of a larger space because of the 'magic' they experience. I can't say that i'm any more right in my opinion than they are in theirs.
It's really going to come down to what you value and consider magical. I tend to stay in timeshare condos when I visit. If you have kids, IMHO, The ability to send them to bed in their own room, then either stay up later and have some adult time without worrying about waking them up.... Or even to have my own room with a door to sleep in, could be considered magical on it's own. Some people might also consider the idea of having a 2nd full bathroom in a 2bdrm unit magical in the morning since you don't need to play the same level of bathroom bingo getting everyone showered and ready in the morning out of 1 bathroom/shower.
