Another thought: be careful buying that upgrade fork; many of them now are tapered (fork is bigger at the lower end of the steerer tube), so if you have an old 1 1/8 straight steerer tube, it will not fit. And fwiw, it is the way forks are going -I just upgraded my old old 1990's mtb last year with a Manitou R7 -I didn't have much choice for a straight steerer with QRs (at least over here) -though since I only paid about 150 quid including shipping and it's an excellent fork for me, it worked out nicely).
Another issue is to be careful to purchase a fork for the right type of wheel you have -e.g. if you have the old style QR dropouts versus the new through axle design, you may need a new through axle hub laced up...... Again, I think you'll be getting less and less choices of QR as time goes on.
I was definitely fortunate to get my Manitou when I did for a straight steerer and QR; I don't anticipate upgrading the fork again as when I'm ready, I wonder if there will be any straight steerer/QR forks left on the market.