My first piece of advice is that if you love to stay in Starwood hotels, and do not already have a Starwood AMEX card, to find as generous a signing bonus as possible (visit FlyerTalk for this) and start using the card for everyday purchases. You'll rack up 1 SP for every dollar you spend on the card for $65/year. If you spend $30k on the card per year, you'll be automatically upgraded to SPG gold.
Secondly, I'd advise you to rescind today, and do some thinking and number crunching. Regardless of what the salesman told you, the same deal will be on the table next week, but the ability to rescind will not. So relax, and take your time to really determine how this timeshare purchase is going to impact you and whether it's right for you.
You said that Starwood hotels are a big draw for you. That means that the ability to convert your 2 bdrm into StarPoints is probably a big draw for you. You should know a few things right off the bat:
1) SVO has never increased the number of SPs owners get for converting their timeshare. If history is any indication, if your timeshare converts to 72k SPs today, in 5 years it'll still convert to 72k SPs. So as time goes by, your value will decrease, except in the unlikely event that MFs decrease.
2) On the other side of the equation, Starwood is continually updating its SP redemption chart. If 72k SP will get you 5 nights in a Category 5 hotel today, in a year or two, it may only get you 4 nights.
3) Some SVO timeshares have already reached the break-even point where it is actually just as cheap (or cheaper) to purchase SPs directly off the SPG website, than it is to convert using a timeshare. So paying tens of thousands of dollars to buy from the developer may ultimately only give you the ability to buy SPs at the current market rate.
That being said, WLR is probably the cheapest way to get 148,100 points from the developer. But, as others have said, there may be more fiscally prudent ways to achieve the same goal. For instance, you can buy a resale 2 bdrm at Sheraton Desert Oasis worth 148,100 SPs for ~$1500 FIRST and THEN go buy the same WLR unit, which Starwood can grandfather into the SVN program for no additional dollars (though you may not have the ability to convert the SDO unit to SPs. Not sure about that). That's the current best approach for getting the most bang for your buck if you're set on buying from the developer.
The key is to do research so that you're buying with your eyes wide open. Many of the bitter posters here have bought from the developer and didn't fully explore the risks of owning. IMO, there are two huge downsides with owning at WLR for you: 1) If you want to sell, you'll be lucky to recoup a fraction of what you paid because it's a voluntary resorts; 2) It flies in the face of owning where you want to buy. Exchanging into a ski resort during ski season is NOT as easing as calling up SVN and saying, "Hey, I have 148,100 SOs and want to exchange in." Having the right number of points is actually the easiest hurdle to overcome, especially now that SVO allows owners to bank their points for future years. I daresay you'll be lucky to get into one of those prime weeks EVER, let alone repeatedly.
BTW, welcome aboard! Wishing you many happy vacations no matter what path you choose.