There are some things you should know.
The reservation will likely be non-refundable and non-cancellable - you need to be SURE you are going.
The reservation remains 100% in the hands of the owner - most turn out fine.
DVC rooms tend to book faster than regular hotel rooms - you should make your plans well in advance of your trip. Also, for the most part, lower cost rooms (such as BWV or BLT standard view) go VERY quickly - budget for the higher priced rooms.
DVC rooms will not come with daily housekeeping - your towels will get switched out on day four and if you stay longer than a week, you get a cleaning on day 8.
I'd say its definitely more complicated - especially if you try and find an owner yourself (rather than working through a broker who will try and find an owner for you). But the savings may be more than worth it IF you are sure you are going to take the trip when you book and can plan ahead.
If you want the Dining plan, you'll need to work with the owner to have it added - you won't be able to do that yourself. Also, changes to your reservation will likely not be possible - no "airfare is better if we leave on Tuesday, lets move everything back one day.
Upgrades are almost unheard of.
Once the reservation is made, you show up and check in like any other Disney reservation and with a few exceptions (housekeeping, studios will have a Queen bed and full (?) pullout rather than two beds), it will work like any Disney room.