True, but take a few minutes to load Xampplite on your PC and develop them there (you can copy your current site down to it db and all so you don't lose context). I didn't do this for the longest time, but could not consider doing it any other way now - changes are instantaneous as you can execute straight from your development code. And latest Xampplite includes PHP 5 and MSQL 5 so you can get ahead of the game testing-wise too.
If you really want to cover all bases, download the deprecated miniXAMPP too and run that with PHP 4, MSQL 4 and 220.127.116.11, and switch back and forth.
Neither miniXAMPP or Xampplite touch the Windoze registry either, so installation - and later removal - are easy. Or even put it on a thumbdrive.