A key point is speculation -- as of today, there is no 2016. There will be one day, but here's the problem you have (and that I did): Say you cancel your 2015 now or even the day the 2016's are announced. Dealers will not be able to guarantee a rapid or even normal delivery to you when there is a MY changeover -- initial allotments vary to every Dealer based on numerous factors beyond your control, and most are pre-configured by Lexus NA and IMHO sort of shipped to them without an ability to order exactly what a Dealer wants. My point being, it may normally take 5 months to deliver a special order, but it could take longer at the outset of a new gen, and initially when the Dealer does put in the special order, they must wait until they ultimately get an "accept" from the plant that the order has been worked-in to their allotment down the road -- which happens (or at least used to) once a month, so where you order can cause that to seem longer than it really is...

Similarly, if history repeats itself, Dealers won't have a lot of information or the ability to order what you want the day of, or even within a couple weeks after a new model hits some trade show. I had more information than my Dealer did for the first couple of weeks because of this site and the internet. It eventually all caught up, but required my sales mgr to effectively take over the deal and manually work it through with Lexus NA outside even a Dealer's normal ordering process. Regardless though, there will be minimal information on the true details of the changes between the models -- sure, we'll have some glossy brochure stuff, and some people will have seen one at a car show or talked to a Dealer insider, but not the detail that may be trusted if you care about that for quite some time and the first vehicles really hit US soil. E.g. we debated here for months about headlight functionality and it wasn't until I received my RX450h (which I think was the first one anyone reported on these forums) that I, my Dealer, and these boards knew lots of little things like if AFS was in the 2013 LEDs, what happened to the tonneau cover changes, little tweaks to the Infotainment Systems that happened, and other minutia. My RX in-fact is a tiny bit of a one-off having rear seats with 2012 clips to accept the full tonneau cover, but my tonneau cover itself is the new 2013 version that has no little flaps connecting to the back seat -- oddities like that may occur wen being first in a new MY. Early-on there is also nothing but maybe a glossy brochure version of new interior or exterior colors that may be available, or e.g. exactly how the leather (it is one tone or two-tone and where do the colors change?), carpet, and side panels look with certain colors -- and we'll likely find discrepancies in pictures between the US site, the brochure, the Apps, and what ends up being reality when the dust settles. You won't be able to physically look at one on a lot and come to a determination perhaps for a while -- if you're (and your significant other if he/she is in the picture) are OK sorta winging that and have good visualization skills and are OK with perhaps a little variation from what you thought you may get, great -- otherwise, it's a problem you can't get frustrated with your Dealer or Lexus about if you want to be first in the line for a new or refreshed MY. ;-)

I personally buy the best car I can for myself at the time, with intention of keeping it 6-8 years. I don't emotionally buy off the lot or flip them like disposable assets as some people seem to, so it is best for me to get exactly what I want and always buy at the beginning of a new or mid-life cycle because of how IMHO that tends to impact ultimate resale value later on. Sure, buying the last of a particular MY may get you the best price today, but if you keep your car a longer time like I do, you could find you're not just one, but two generations back in it's looks and capabilities. In the case of my 2013 vs 2012, that refreshed spindle grille made all the difference to me -- not because I was sold on it's look (still really don't like it), but because if I had a 2013 it would look "current" for a longer period of time while I own it, than if I had gone with the 2012 that would have an outdated look the day I took the brand new vehicle off the lot. I'm also a research hound wanting to know what I'm getting before I sign on the dotted line, so I have to work with myself coming to grips with how much I'm willing to not know before I get the real thing home in the garage. ah ha.

In the case of my 2013, my Dealer was understanding, and basically ate my 2012 (which they sold a day or two after it hit their lot because it was more fully optioned than nearly anything they ever have, so they knew they'd rapidly sell it unlike some oddball configurations some folks may order). The sales mgr allowed me to place an order for the 2013 -- so my clock started over on everything, BUT I was literally in the first shipment from Japan to the US in delivery of my RX450h, so that was sorta exciting. Being first though prevented me from having BSM most other 2013s with the luxury pkg have because it didn't come out for about 3 months after the first shipments began and I just couldn't wait almost 1 year in the total process... I love that feature on my MBZ and regret not having it on my RX. Also, I had to place that order for the 2013 with a lot of handshakes and trust with my Dealer, because they didn't have a clue on their costs until it hit a ship several months later so we couldn't renegotiate -- and I like to have my out-the-door price predetermined at time of order so I don't have surprises. It all worked out for me in the end and given similar circumstances I would do it the same way again today.