have you seen those faucets IRL? the amount of water that comes out is equivalent to the spray on a drinking faucet. at least mine is! there's no way you could wash vegetables or use it as a prep sink faucet -unless i'm missing something and we're not talking about the same thing. (?)

either way i think you could still fit one in with a regular faucet. there are a lot of smaller faucets available for just this purpose. GL!

Rohl makes a "tri-flow" faucet - hot and cold plus filtered. They also have a set with sprayer. Don't think it is "insta hot or cold" tho. Many styles. Considering it for my prep and bar sinks.

Here is a link that might be useful: Rohl Tri Flow

All the insta-hot faucets I've had require you to hold down the "handle" to get the water to flow. They don't stay on if you let go...at least the ones I've had didn't. And the water doesn't flow at a high rate. Probably for safety reasons as you wouldn't want splashing with the hot water.

The no flow with release is a design safety thing on the instant hots so I doubt you'd find one like that. The water flow on them is too low for a prep sink. I am not familiar withthe Roghl, but that looks like a good idea. If you don't need a soap dispenser there, maybe you can do a faucet on one corner and the instant hot at the other. I have a smaller sink with corner faucet and corner soap dispenser that makes me thinl that should work too.

We have an instant hot/cold faucet now on our main sink that does stay on and that has a high flow rate. It works very well and I would not hesitate to use it as a prep sink faucet. The flow rate on the cold water w/ chiller is just as fast as at my nearby faucet at the same sink. It is very different than the other ones I have had in the past where I did have to hold down and/or where I only got a trickle of water.

This is it:
http://www.amazon.com/Westbrass-D205-07-Victorian-Dispenser-Traditional/dp/B005CFTM84

The cool water handle on our filtered hot and cold faucet does stay on if you open it all the way. Only the hot one needs to be held down. The flow rate is reasonable. However, I don't think it would make a good substitute for a prep faucet. For one thing, the reach is short - meant for just putting a cup or whatever right under it. No spray function.

You could easily have enough room for both a regular and hot/cold filtered faucet at a 20" sink. The instahot faucets are usually pretty small.

Our instahot is at our main sink but the left bowl is 20" and the right bowl is much smaller so the picture may give you some idea how both would fit:

Hi everyone, thanks for all of the input. I guess the instahot probably wouldn't be a great idea since I would need some sort of safety mechanism on it because I have twin toddlers. I know it would annoy me to use it as the only prep faucet if i had to have low flow though. if i could use a faucet like beaglesdoitbetter, and somehow install a safety mechanism that doesn't involve low flow, maybe that would work. but i have to do more research on this. i remember seeing a thread about tapmaster used for this..

michelledt, the triflow faucet sounds pretty interesting. maybe i could make do with cold filtered water for soup. thanks for the suggestion! i will look into it some more.

cloudswift, thanks so much for the pic of your sink. i think the two faucets on your sink look fine because you can tell the other side is spacious. I am not sure it would work as well for my prep since it is on an island. i will have to do some mockups to see. btw, what is your granite? it is so pretty!

Thank you. Our granite is Azul do Mar. It is really a quartzite as are many of the stones with very definite blues.

Here is a picture of our 20" prep sink with soap dispenser and faucet. There would have been enough room to add the instahot especially if we were only using it from the front. We considered putting it here, but both it and the main sink are about the same distance from our rangetop and the main sink is closer to the baking and coffee/tea area where we also use filtered water. And because it is on the island corner, we wanted to keep down the clutter and we also wanted to keep the accessories in the inner corner so that the sink can be used from both sides of the corner.

Our tap water quality is pretty good, not high chlorine so it's fine for soup or pasta anyway but I usually use the filtered.

michoumonster: having little ones around really wouldn't deter me from putting in an insta hot. my kids are eight and nine years old and they still can't reach the faucet. a range top or oven is more dangerous, imo. GL!

Agree with all above who say the instant hot or cold won't work as a prep faucet -- the flow is just not strong enough. Even on the instant cold, which does have reasonably strong flow, I would not want to be washing a lot of fruits or veggies in it. It would be a pain.

Not sure why you couldn't fit both faucets in a 20" sink. We have a prep faucet, an instant cold, AND a soap dispenser in our 15" bar sink and it functions perfectly.

Granted if you are going for a sleek or minimalist look then I wouldn't do it, but we wanted function over form and I'm so glad we did it. Here are two pics to show how it looks, so you can judge for yourself if it would be too cluttered for you (but bear in mind this is a 15" sink and you will have an extra 5" to play with on top of what we did):

cloudswift, thanks for the island pic. that is so neat that you can pull your faucet all the way to a pot on your range!

kateskouros, thanks for the practical advice on the instahot with little ones. i didn't think about the fact that they cannot reach it, haha! my kids are 10th percentile on the growth charts, so it will be a while before they can reach the faucets. i can always turn down the temp of the hot for a while too.

taggie, I am going for a sleek look, but functionality is important to me too. thanks for sharing the pic of your bar setup. your kitchen is really elegant! two faucets at your sink definitely look fine. i need to have a soap dispenser and also air switch at my prep sink, but maybe i can work in a small faucet.