QUOTE(Halia @ Mar 14 2014, 06:34 PM)
To chip in my opinion on gear upgrading. I assumed the no.1 reason of upgrading from 8/9 speed to 21++ speeds is to help climbing. I am in the opinion that such thinking/rationale may not necessary 'sound'. The OEM 8/9 speed in most cases are sufficient for normal climbing fits for what the original intention of the bike is for. Sure, if one to take his/her folding bike to Genting and the like, he/she may finds 8/9 speed is insufficient. The question is how likely are you going to ride on Genting-like road? Even you do so (like more of the advanced cyclists), more gearing can only helps you to certain level, your up right seating geometric is 'hindering' your climbing efficiency, you will still find yourself struggling. If your are not struggling, it is likely that the climb is not steep enough and the regular 8/9 speed with reasonable fitness would just do the job fine (if you are not reasonably fit you probably won't attempted to steep climb type of ride). In the 'normal' outing rides, even there are some parts that are steep, it usually just a short climb, you can just tahan a bit and ride over it.
In most of the situation, 8/9 speed can climbs but what is lacking is the flat road speed. Therefore, instead of looking at increasing more speed, it make sense to have a bigger crank set, like 52T for the flat road speed. Frankly, easily 80-90% of the ride are on flat road.
Make sense?
There are some points in your comment but it takes many types of riders to make a community just the same as there are many types of people in this world. But I will start with why I always mod my foldie to the max, especially on the drive train.
Once you join a group or groups and ride very frequently, you most definitely will improve and the rides will even be longer. If you say extra gears is not really a rational or sound moves, I will beg to differ in my case. The rides I ride with a few groups may last the whole day and in some occasion continuous 3 days. When I was riding Genting Peras, I started with an Eco C7 and the amount of effort to ride up , it's possible but it's also killing.

While others did it in an hour or so, I did it with my wife in over 2 hours. Later when I added another chainring, I am able to improve on my time and later when I did Fraser's Hill, I added another one after I came back from the first Fraser's ride.
Sometimes, when we are tired, we just need to 'cruise uphill'. We need to rest our legs a bit although we are still riding uphill. So we tend to ride easy but it is slow. We are like resting but still moving. If we are still on 8/9 gears, we have to stop as the lowest ratio, we still need to push hard! So, if we stop and rest, our muscles will relax and it will be hard to start again.
To sum it all, I have 3 chain rings on my Speed and 2 chain rings on my Dash. BUT I use the biggest most of the time and very rarely I use smaller chain ring (this concurs to your comments) BUT I also need the smaller chain ring there, just in case. Least but not least, there's a reason why folding bike companies comes out with 18 speed and even 30 speed folding bikes. It's just that, you need to figure out WHY do you need the foldie for? Off course if it is just to ride around the park and sweat it out, a single speed would suffice already. If you go on long rides, unfamiliar routes, the more gears I have the better prepared I am for it!