After about 10 months the pressure significantly declined. I thought I might just need to replace the prefilter so I did and it made no difference. I'm guessing the membrane may be done, that or the holding tank is done. Right now the water comes out of the faucet at a flow marginally faster than when I first installed it and tested it to see how it worked and flushed the tank. So I don't know but it takes so long to fill a cup of water I end up drinking less of having the cup spill over cause I go do something else while I am waiting.

I will say I have a very high iron content in my water so maybe that clogged the membrane but replacing the membrane every ten months would not be feasible it should last close to 3 years.

Very happy, we can drink our water again!

I installed this in the basement, and plumbed it to both a sink tap (I had an existing I re used), and refrigerator.

I plumbed this in after our whole house softener. We're on city wide well water. It is treated so I wasn't too worried about contaminants, this is for taste.

At first I was pretty disappointed with the water taste, after draining the first 2 tanks off. After reading the manual and making sure everything was installed correctly, I picked up the tank after draining it through the faucet, and found I wasn't actually getting it empty, it was flowing so well I couldn't drain the tank! I disconnected the tank and drained it off by itself.
Since then, water quality and taste has been excellent. We haven't bought bottles of water since.

I have a family of 4 and at first thought the 4G tank would be too small, but it hasn't been an issue.

My only complaint really, is that the "upgrades" aren't well communicated. After purchasing the kit, the manual shows a 3/8th line upgrade I would have bought had I known about it.
Also they don't really state that it only comes with a bare minimum of lines, though I do realize they expect this to be under the sink near everything. I was able to find 50' at our local hardware store to get this installed.

I installed the ULTIMATE RO-90 about 4 months ago. What attracted me to this product was: Good reviews on Amazon; Price and features; Amazon Prime availability; Made in USA; and excellent pre-sales customer support (I asked some questions before purchase). I have had two other RO units in previous homes (one installed professionally, one by myself). This APEC unit appears sturdy, as well made or better than my previous much more expensive professionally installed name brand unit and definitely better than the self installed big box store unit.
I decided to use the RO-90 to feed RO water to the countertop faucet which comes with the unit as well as run a line to my built in refrigerator using the separate APEC kit (ICEMAKER-KIT-RO-1). I decided not to run the RO water to my ISE Instant Hot Water tank. The ISE unit has a copper pipe in the feed line to tank (I didn't want the RO water going through copper). The ISE unit also discourages anything other than a direct feed from the cold water supply. It may be fine to run the RO to the Instant Hot Water unit but I decided not to do it for now.
The undersink photo will show the installed unit. I had to figure out how to tuck in the filter housing and tank along with the ISE Instant Hot Water unit, an ISE air switch, and the ever present disposer. If you look closely, you will see the RO drain saddle going in to the top of the horizontal piece between the disposer and main P-trap. This alternate design drain saddle was sent to me by APEC at no additional cost after I couldn't fit the original plastic unit well. I recommend installing the drain saddle on the horizontal drain pipe because it is much quieter than on the vertical tailpiece.
Anyway, the water tastes great and I know the unit is working (TDS of ULTIMATE RO-90 water = 17 ppm, my tap water = 374 ppm using a HM Digital TDS-4 meter). My family and I are very happy with the water!

I was having problems with my older Kinetico RO system - the water output was slowing. The local dealer suggested replacing the $75 filter set, but that did not fix anything. Next I paid for a service call - another $80. The tech tried some things, but told me I probably needed a new membrane - the PART would be $500. I actually considered it. After all, the Kinetico system sells for $1,100 and I keep hearing that it's the Cadillac of RO systems. It must be great, but come on! And don't forget the mandatory filter changes at least annually. Did I mention the filter set runs about $75? But it also goes up every year.

I ordered the APEC high flow 90 system primarily because the unit has a membrane manufactured by DOW. And (this was important to me, too) almost all the parts are made in the USA.

Amazon prime delivered the new unit faster than the local Kinetico store could have set up an appointment with the installation tech. Installation was simple, especially since I was replacing an existing unit. The instructions were VERY well written and thought out. The hoses are color coded to help you get everything right, and just in case they include a full color 8x11 picture showing the complete hook up. It went together quickly and without any leaks.

The high capacity on this unit recharges the tank quickly. We only have two people in our household, but run the fridge ice maker though the RO system too. We never run short on RO water.

I have no reservations in this purchase. I would highly recommending this APEC High Flow 90 RO system. I think you'll be happy too.

I had entertained some quotes from various establishments to have a reverse osmosis system installed in my home. Was shocked at the prices I was given ($850.00 to $1,200) so I decided to do some research on the internet. Determined that it wasn't that hard to do myself. Shopped big-box retailers on line and thought that most of the units they were selling were cheap. Looked up on Amazon and found this unit and was impressed with the product. Went to APEC's website to learn more and determined this was the unit I should buy. Liked the fact that it is manufactured in the U.S. It was very easy to install and the water tastes so much better than what we had. Noticed that the water boils faster when we are cooking and leaves no disgusting rings in the pan. Also purchased the Icemaker kit and ran it to our refrigerator. Don't need to use the water filter in the fridge anymore and get clearer ice cubes. I recommend this unit to anyone who would love to have better tasting water and get rid of buying bottled water.