Hey I'm a newbie to folder and I recently got hold of Dahon eco 6.
http://dahon.com/mainnav/folding-bik.../eco_c6-2.html
I will be using bike for commuting/riding for fun.

And I'm looking to get some upgrades going, starting with either pedal or BB/crankset.
(mostly since I'm not funded enough to go with hub/wheelset, cassette, shifter route)

As of pedal, I saw many recommend mks folding pedals. I'm shooting for below 50.

For crankset, I honestly have no idea what is installed as default in the bike (my friend who agreed to hand it over is coming in few days)
price has to be close to 100 or lower and hopefully it keeps the original gear T or lower so i won't need to get a new chain.
I'm actually planing to get 9 speed for further upgrades.

1. So is it worth it to get these upgrades?
2. can 9 or 10 speed crankset be used for 6 speed drive-train?
3. what T would I need to get to fit the chain?
4. any recommendations on parts?

Thanks!