i use salon 4 kids on maple street in summit
 
After a horrifying experience with my daughter at Kids Cuts at Livingston Mall, I started taking my kids to Subway where I go.  All of my friends take their kids there also.  It is more expensive, but I try and go on a Tuesday or Wednesday when it's quieter and they love the kids and the kids love them.  I go to Kelly, she is great
 
After years of getting not great haircuts at Kids Cuts in Livingston, I started taking my boys to the barber shop on Millburn Avenue. I think they do a very good job
Two mom's from town opened a salon geared to kids and teens called The House. It's on Essex Street, diagonally across from Nancy and David Jewelers.

Did you try KidsKuts in the Livingston Mall.  They used to be $20.

My 7 year old son loves the barber on Millburn Avenue.  We can just walk in, and they really listen to what my son, or I, want and have given him cuts as good as the ones we used to get in Manhattan

We use Salon for Kids in Summit on Maple St. They do a wonderful job
 
we've had luck w/ Robert at Kids Cuts in the Livingston Mall. this place is well recommended, and we were happy with it for my 4 and 2 year old. Can't speak to cool cuts for six year olds though 
 
We go to Kidz Cuts in the Livingston Mall. They take walk-up appointments, and sometimes you do have to wait if it's a busy weekend afternoon, but usuallythey can take you right away. They've got videos and funky kids seats (car, airplane), and have givenconsistently nice cuts to my 5-year old daughter. My husband usually takes my 2-1/2 year old son to the barber right in Millburn.
 
Salon 4 Kids
44 Maple Street
Summit, N.J. 07901
908-598-0800

(I've had not so great experience with kids cutz by the way--I think you need a name or else there's no guarantee about who you'll get--I've got one older woman, who has done a really mediocre job)
 
After using a kid's haircut place in Summit because Eric was very difficult when he was little, and then paying a small fortune for haircuts for Andy and Eric at Subway, we discovered everyone else was taking their boys to Michael's barber shop in Millburn.  Colleen does most of the young boys' cuts.  She's a little quirky, but great with kids.  There's a young guy, I've forgotten his name, who cuts Andy's hair, and does most of the trendier cuts for the young men.  The owner, Michael, cuts Rich's hair.  They're very nice and do a good job, they're quite reasonable, open a lot of hours including Monday and there's even parking.   
 
Both my boys used to go to children's haircutters where they play movies and sit on fancy chairs. I found that the places that specialized in children were hiring inexperienced haircutters and as soon as they got experience they left to cut adults hair for more money.   My boys are now six and ten and for the last four years my husband has been taking them to the Barber Shop in Millburn.  They are reasonable and they have been getting much better haircuts and you don't need an appointment
I started getting my kids' haircuts by Sue at Rox-Hands about 3 months ago. It's on Lackawanna (just down the street from the diner a few doors up from Millburn Ave.). Sue cuts their hair. I found it b/c I needed a manicure once and I went there and the new owner told me that this woman did a good job on kids. We have been very pleased. And...it's pretty inexpensive, I think $15 per kid. No airplane chairs or videos though ;)

Avoid the Millburn barber. I cannot be more emphatic about this. Over the years, my son, 7, has had a few haircuts there, usually out of desperation. Each was awful, but the last one could down in record books as the worst haircut ever. He was rendered bald. Two months later, at least it has grown into a buzz cut, but I will never allow him in there again. I have had mixed luck with the Kidz Cuts at the Livingston Mall, though the noise level is terrifying

One day we stumbled upon "Miracles" Salon. They are a nothing-fancy kids salon on Morris Avenue in Union -- right across the street from the Walgreens. I think it's near Caldwell Ave? As far as I can tell the owner is the only one there, she is reasonably priced, her hours are good, and she's great with kids. She does take appointments, but we've always walked in (sometimes with 3 girls needing cuts.) There's usually no wait to speak of, although once I waited close to an hour. I could have left and come back, but the kids watched a video... Since we've found her, we've never gone back to Super Cuts or Kidz Kutz

The place I like for my younger kids (1,3) is Salon 4 kids in Summit but it is more of a bells and whistles place for little ones.   The Super Cuts on Morris Ave near Panera will do kids for around $15 and takes last minute appointments.  The cut they gave my son was fine but not as good as Salon 4 Kids who is more like $23 for a cut.  Even though he's just a kid & doesn't care much about the cut, for me the more expensive cut is worth it because of the way it grows out nicely, I don't have to take him in as often.
 
I also used Cuts for Kids in the Livingston mall ( I think that is the name) and they were better than SuperCuts but not as good as Salon4Kids