Ooops. went to AD ... leaning toward another purchase: Stay, Trade, or Buy?

[Elusion]

I went to an AD this weekend and it really made me want to pull the trigger on a BLNR, which I’ve loved since they debuted.
I’ve had a Subc (114060) for almost 3 years now and love it. I wear it every day. I also have a Speedy, which I got around the same time, but it's been over a year since I wore the Speedmaster.
I've wanted a GMT since I got my Sub. My wife even asks when I'm going to get the GMT, since I’ve been talking about it on-and-off for almost 3 years.
But the Fiscally Responsible part of me always keeps me from getting one; I keep thinking of my Kids College fund and the fact I don’t really make ‘rolex money’.
There are a couple other watches I like but not as much as the GMT: Master Controller, Tudor Heritage Chrono, Zenith El primero.
So,
Should I be content with my Amazing pair of Classic watches?
Trade my Sub in for a GMT (my wife is against this idea)- she is not a frugal as I am.
Get the GMT and live happily ever after …. Until my Watch interest is sparked again and run the risk of my Kids having a crappy education.
Get a less expensive watch?