kenny.bacon- IME how well water works for glass is pretty dependent on water *quality*. Really hard water isn't something I want on my glass
The water "quality" that you use does, indeed, make a difference. I know some of you use distilled water that can be purchased at most major grocery stores for about $0.75 per gallon OR de-ionized water from water-treatment /softeners like CR Spotless.
I use the water from my home de-humidifier for cleaning. Granted, it is NOT truly "distilled" water, but you'd dump that water down a drain anyway, so why not collect it and use it? Chances are most of you reading this have a de-humidifier somewhere in your house.
I've used Stoners Invisible Glass (SIG) and it is OK. Currently I use Sprayway Glass Cleaner. It's OK, too. I've yet to try Meg's Detailer Line Glass Cleaner Concentrate D120. Seems to get a lot of good comments and recommendations for that bulk glass cleaner.
I've tried using 91% Isopropyl Alcohol (IPA) on a dedicated microfiber for the initial cleaning of glass to remove any oils, plastic/vinyl gas-off film, and cigarette smoke film residue. Works very well, BUT you do need to follow up with some type of cleaner, either distilled water and a good, clean glass-cleaning microfiber to remove the streaks. Still use Bounty paper toweling due to its absorbency and the fore-mentioned Sprayway, but I know that some of you do not like (fine) paper lint it leaves behind.
On the subject of microfibers, my wife attended a Norwex microfiber party (similar to a home Tupperware party) and got roped into buying the glass cleaning towels. She paid an exorbitant price for a two-cloth system and the soap to clean them, but they do work as advertised. Their claim-to-fame is their proprietary silver-infused fibers, that are naturally anti-bacterial. Not sure how this applies to glass-cleaning microfiber clothes. The first cloth is used for cleaning and feels like a premium nap microfiber that you use clean (distilled) water with to wipe off any "contaminants". The second cloth is more like a traditional glass-cleaning cloth with no nap and used for the final wipe-down to get streak-free glass. Like previous posters have stated, keeping these cloths separate from other microfibers during cleaning is key to keeping them contaminant-free. These clothes are to be cleaned by using Norwex's dishwashing soap and boiling water to clean them. I've done that, and yes, the first cleaning cloth does hold a lot of contaminants that are released with the soap and boiling water. But for the price I could buy ALOT of paper toweling and Sprayway cleaner OR some quality glass-cleaning microfiber cloths. It is an eco-friendly way to clean, though, using clean (distilled) water.