The Typhoon III isn't a bad unit either, but I personally had issues with it (including a membrane chamber started leaking causing high TDS). Replacement higher quality parts (chamber was much more solid) from Buckeye fixed the issue. Not to bang Airwaterice as they are a solid company with a lot of great feedback, but issues can occur.
<a href=showthread.php?s=&postid=15278372#post15278372 target=_blank>Originally posted</a> by slathrum
This is the one area I go cheap. Case in point - my $90 shipped new 6 stage www.purewaterclub.com unit continues to crank out 0 TDS. The housings for these things all seem identical while everyone with their twice as expensive unit will claim theirs is superiorly constructed. It may have a bunch of doo dads and junk on it, but none of that is really necessary for making 0 TDS water. The inline meters never seem very accurate compared to a handheld and a pressure gauge while helpful really isn't necessary unless you're wanting to boost your output with a booster pump on a higher GPD unit. What it comes down to is the filters, and most of those look pretty darn similar between the cheapies and expensive ones. I'd almost guarantee my membrane is made by Filmtec and packaged under a different name. Skimmers, lights...don't go cheap or without doing your homework because you'll end up paying in the end, but RO units are a dime a dozen and nothing special. I always get crap on this, but it really doesn't matter when my unit has failed to self-destruct or not work as well like everyone seems to think.
As with my previous comment, there are major differences in parts, even between quality vendors. No offense, but as you said, most of us could go on for paragraph on paragraph listing issues with most of the rigged up ebay units including the one above (drinking water primarily and very poorly rigged up to try to meet reefkeeper's needs). I'm glad it seems to be working for you, but I wouldn't necessarily recommend it to anyone else. Low quality parts, vertical DI, outright wrong information on the site including specs of parts, tons of extra filters that aren't needed, increased cost (and often much more expensive long term than starting with a quality unit in the first place) due to poor DI usage and extra filters to replace, etc, etc, etc.
Basically many people are happy with these units, but I probably wouldn't use one if you gave it to me for free. And again, please take no offense, but I feel this statement below is 100% dead wrong. RO/DI and water quality in my opinion is one of the most important aspects of succesfull reefkeeping. Some are blessed in having almost perfect water out of the tap and can use rigged up systems. A good chuck of us however do not have the best water possible from the tap and would spend a fortune replacing filters and DI on the system above, or potentially crash our tanks if emphasis on RO/DI was not in place. Just a few of my inhabitants warrant spending slightly more money up front for a properly built system (and will likely save me more money in the long term), let alone the cost of potential issues with all my prized fish/corals/etc.
<a href=showthread.php?s=&postid=15278372#post15278372 target=_blank>Originally posted</a> by slathrum
This is the one area I go cheap.