... I am not really concerned about Taq, coming from an extremophile,...
But you should be concerned about the TAQ, if not stored properly its half-life is hours and, considering costs, is the most expensive reagent. The dNTPs are also sensitive, but not as the TAQ. The other reagents are usually buffers and salts, you don't have to worry about those.
At BIO2007, i saw a company (i don't remember the name) that was selling water with some other reagents, they claimed that those would keep the reagents for PCR stable at room temperature and give a longer half life at 4C, sadly we were there as the booths were closing, but i think i still have some info at work, that may be a good option.
Mario