Sundeal rides pretty well, I've put about 200 miles on my other minibike, JAVA; commuting between Brooklyn (Coney Isl.) & Manhattan.

The Sundeal has taller gearing, which is more difficult for city commute that sometimes require hopping onto the curb to avoid car traffic and pedaling among foot traffic.

I like having smaller gear to ride a walking pace and easy acceleration from low speed, which is crucial for a commuter bike in traffic pattern like NYC.

I hardly ever get above 17-18 mph, because chances of serious injury is much higher at speed above that in NYC traffic.
Sundeal has nice wide tires, keeps the momentum once the bike gets up to speed, like heavier rims.
Bike with smaller wheels lose momentum really fast whenever you're not pedaling, heavier rims or tires will keep the momentum better for them to ride like bike with larger wheels.

Handling/steering of Sundeal is very similar to my JAVA minibike, steering is quick at low/walking speed, but once above 12-15 mph, they ride pretty much like a full sized 700c bike. But you have to make sure that the stem is sized to suit your riding. OEM stems on these bikes are usually too short/low for adult riders.

I'm 5'9", I ride my minibikes with 130 or 140mm stems 17 deg rise, longer stem also slows the steering for minibikes.
My commute also involves taking the bike onto a train to cross from NYC to NJ; minibikes or folding bikes take up far less room on the commuter train and little lighter to carry up and down steps to get to the train platform.

For the winter months I ride my folding bike and get on and off NYC subway train with my folding bike, 16" wheels are slow, but still beats walking.

'Hopefully, I get to put some miles on the Sundeal soon.

So far I've only put it together and test ridden it around the neighborhood for riding position feel..
You have to set your expectations with these minibikes, they are not meant to ride like a full sized road or mt. bike. Not meant for speed work in a paceline. If you want to cruise above 20 mph most of the time, look elsewhere.

If you have limited storage for a full sized bicycle and ride among city traffic, smaller, lighter bikes make sense; they take up less room when not ridden, less chance to get hit by car when you are a smaller target. Fatter rims/tires with small sized wheels will survive the potholes better.

For $139, the Sundeal is a very good deal for what you get, good baseline bike that will likely last longer that most department store bicycles. Good solid frame, decent riding geometry, important components are quality items.

It's not going to ride like a top of the line bike, but after working in the bike industry for over two decades; this one is a sold bike IMO.