It is a hard position to be in. Firstly, if this has been your grail watch for 3 years, and you have always wanted one, your desire for the watch will not disappear.
Secondly, will you think in a years time, 'I wish I had that Daytona on my wrist now, instead of that clapped out rep I bought that is now sitting in the drawer' or 'I'm glad I still have that 10k in the bank to buy another rep Daytona'? If it is the first buy it.
Thirdly, what would the resale value be like on this watch (I am not too knowledgable about the Rolexs). If the resale is good, and in a years time you think the second of the two thoughts, you can always sell it on.
If you are in a stable position, with a secure job, and you can afford to buy the watch, without having to worry about how to pay the next bill, go for it. At least then you will have experienced your holy grail watch. If it doesn't meet your expectations, then sell it on. However, I have a big feeling that you will love it, and in a years time, be looking back on this night as the turning point in your watch collection, and have one of the most sought after Rolex's in your collection!