I agree about if you're going to do one, go with Marriott.
You can even call them and see what they have to offer. We own at Marriott (Ko Olina). They are less pressure, but still you have to go in with the right mindset if you're not going to buy.
They are not a scam at all with that company. Just understand the details, cancellation policy, etc... ahead of time.
Also, if you have any friends that own timeshares that trade with II, you can have them look into getaway weeks. All of the ones I've done in Orlando have been getaways, even over spring break. Typically I've paid about $350 for a week on those. They are prepaid, and you are treated like an owner (no maid service, but I don't want that anyway in a condo), but a great deal! That was how in 2012 we did 15 nights (overlapping weeks) for less than $800.