Tankless RO? What is everyones opinion? Reverse osmosis

There are a few tankless RO systems out there and I am very interested in trying one out but I was hoping for some more info?
What is the outlet pressure after treatment?
Are they as good as storage models?
still install after softener?
Claim up to 1000GPD.

Models
iSpring 400GPD
Evolution Tankless Reverse Osmosis System (1000GPD)
GE Merlin 720 GPD Tankless

Any comments are appreciated.

I notice the merlin 720 is rated at 1/2 GPM. Not exactly a whole-house unit!

It would have to be a pretty "hefty", or inefficient, unit to process the water in ""real time" AND produce 1000 gallons a day, when the average one only does beteen 25 and 50 gpd. Unless it costs several thousand dollars, I would not consider it.

The ratio of waste to RO with an RO functioning perfectly is about 3-1 or worse depending on incoming water temp, that's a lot of water wasted. The GE unit gets by that using dual membranes and it's ratio is still 2-1. You get that efficiency at the cost of 2 X $237 membranes that only last a maximum of 2 years. That's going to end up being some very expensive water.

In most cases a 50 to 100 GPD with a holding tank under the kitchen sink and a dedicated faucet is the best option.