A good folding bike should ride just as well and last just long as a traditional bike.
BikeFriday has a reputation for bikes that feel "normal."
As far as maintenance goes there is very little difference.
From my experience the only thing that needs more frequent maintenance are the cable housings.
This is because cables usually have to make more complex cable bends on a compact folding frame.
This causes the housing wear out a bit faster.
From my experience about 33% faster than my traditional bikes.
bicycles.stackexchange.com/users/15797/Burke Shartsis
There is not really difference in maintenance.
You have the same brakes, gears (rear), shocks, wheels, bearings.
The only addition is the bolts where you fold the bike.
About the commute - folding bikes have smaller wheels, which ends up in: Decreased speed (for people like me who loves high speed
it's significant).
At some point you can see yourself pedaling like a crazy to get a just a little bit faster.
Significant sensitivity to road roughness.
Any bump in the road becomes much more serious.
bicycles.stackexchange.com/users/7999/Alexander
A folding bike just does ride as well and is not as efficient.
Small frame and small wheels.
You are going to pay more for a folding bike.
Brand does matter - some of the high end ride nicely and some low end ride badly.
bicycles.stackexchange.com/users/7785/paparazzo
After trying to live with a folding bike, here are my observations.
Most, (all) foldy bikes have a feel different from a regular road or MTB.
so the feeling is never going to be the same.
There might be some flex from the handlebars, they could be slow or feel as though they are going to fall over....
So I think to a large extent it would be best to put their handling characteristics out of the way.
I think a true measure of a folding bike is: how it folds,how easy it is to walk up the stairs with it,how easy it is to put it in the boot of the car,how easy to walk 10 meters with the bike in its completely folded state.
(or how easy it is to fulfil your portability needs)
Similarly a downhill mtb with 7" of suspension is not going to work so well as a regular street commuter, but in the right environment its horses for courses
bicycles.stackexchange.com/users/15798/Paul Lincoln
Folding bikes are great.
Many higher-end folding bikes have derailleurs or geared hubs, which means that they can be just as fast as a regular bicycle.
The only things that you lose are: Stability because of the smaller wheels.
This can be a positive as a city bicycle as they are more nimble (i.e., less stable) at slower speeds.
Harder ride.
Because the wheels are smaller and the spokes smaller, the ride will be rougher.
The frames are not as rigid and are arguably less strong.
So you won't be able to jump off curbs and do as many bunny hops.
bicycles.stackexchange.com/users/11160/RoboKaren
I own a cheap "metro" folder, and it is quite different riding to a normal sized bike.
The steering is a lot more reactive than a bike with a larger wheel, so it wants to wander a bit more.
This is due to the smaller front wheel, shorter forks and reduced trail.
I can't ride this one hands-free for long, regardless of gear.
Rider Position is much more upright, so you're more visible but more of a sail too to catch the wind.
Overall gearing is narrower because most folders are single front chainring.
This is mostly okay on the flat, but grades over 10% are no fun.
You'll also spin out sooner on the downhill or with a tailwind.
Cranks and seatposts tend to be short too - if you're over 6 foot a normal folder will likely be too small.
Mine is.
bicycles.stackexchange.com/users/19705/Criggie
I am planning to buy a folding bicycle (brand doesn't matter). Intent is commuting to work inside the city (5-6 kms one side run). Reason for folding bicycle is space constraint in my apartment. I never rode a folding bicycle before I am curious to know how different it is from normal bikes riding wise and any additional maintenance is involved and durability compared to normal bikes   Please advise.
Advice on Folding Bicycle
bicycles.stackexchange.com
<folding-bicycle><city>
bicycles.stackexchange.com/questions/27198
bicycles.stackexchange.com/users/15769/V.B
A good folding bike should ride just as well and last just long as a traditional bike. However, they have smaller wheels so require more pedal power to move ahead. The frame is also smaller and less rigid. Brand is important as some high ends ride well and some low ends badly. The steering is a lot more reactive so it tends to wander a bit. As regards maintenance, there is little to no difference. As it is a folding bike, the key question is how easy it folds. The riding feel should be similar with a good quality folding bike, but the small wheels and less rigid frame will make it less stable and more reactive to bumps. The cost is higher than for an equivalent normal bike, but the advantages of size and portability can balance this out. Higher end bikes often have more gears, but the upright position is less aerodynamic. Maintenance is similar, since the main components are equivalent to normal bikes. 
The riding feel should be similar with a good quality folding bike, but the small wheels and less rigid frame will make it less stable and more reactive to bumps. Higher end bikes often have more gears, but the upright position is less aerodynamic. Maintenance is similar, since the main components are equivalent to normal bikes. The cost is higher than for an equivalent normal bike, but the advantages of size and portability can balance this.