That first burst of water coming off the membrane contains elevated levels of TDS, and that reduces the DI resin's lifespan. Watch the TDS meter for the first 60 seconds to see why burning off a minute's worth of water is worthwhile.
This is the regulator I use, which comes highly recommended. It costs about $180 (free shipping when I bought it), and comes with a three year warranty. It's flashing red light indicates when each "bubble" heads to the calcium reactor. The electronic CO2 regulator's black box does the work, eliminating the need for a bubble counter.
Titration water testing was so last year. Using a magnetic stirrer, I'm able to quickly perform test after test and determine the water parameters from each of my tanks. It's amazing, and hopefully these will come to market soon.
The longer you have an aquarium, the more tools you'll acquire. It's nice to know what experienced hobbyists use, and I thought I'd share the stuff I turn to for the various projects I have to care for. You may think of some other things that would make life easier. Your imagination may help you invent the next best tool, so keep those mental gears turning.