A few things happened in recent past that got me thinking on the same lines - return to office seems to be around the corner for me; a random unplanned visit to Pro Cycles where I got to ride around a Brompton for the 1st time; and a stop at Decathlon where I got to try out the BTwin folding bike.
While I don't own a folding bike myself I'm just putting down my thoughts:
1. Brompton: Was very impressed with Brompton with just that 15 min test ride I did. With the big chairing at front it does feel a bit more like a normal ride, but way more fun with that sprightly feel from small wheels. If I didn't have to win a lottery to own one, I would have bought one by now!
2. BTwin folding bike: is not that impressive. I don't know about the hinge quality, frame quality, or longevity but it definitely was not as comfortable as riding a Brompton - the seat height is very low even when above the minimum insertion point and the chainring is small - so it will always feel like riding a kid's bike.
3. Folding time: I personally don't think folding time will matter too much. The typical scenario I think of using folding cycles is for last mile connectivity. So, I would happily trade 2 to 5 min to fold and unfold rather than wait 5 to 10 minutes to get auto/cab/bus.
4. Metro specific: Namma Metro now allows folding cycles (yippee!), but from what I have heard it still has to pass through the luggage screener. I think only Brompton folds compactly enough to pass through them without any hassle. The BTwin will probably not - just eyeballing here. What I have learnt from talking with a few security chaps at the Metro is that if the cycle doesn't fit through the scanner then the security supervisor needs to come and inspect before letting it through. There will also be an additional luggages fee of around ₹30. I am probably okay with the luggage fee (think of it as minimum distance auto fare), but I think the hassle of waiting for the supervisor and explaining the situation is probably not something that I will have the patience for each time it happens. Also, I've read somewhere that the scanner size is not uniform as there are multiple contractors for it and apparently some folding bikes that fit through at one station may not fit through the scanner at another.
5. Price: Brompton does tick all the right boxes, but at ₹1.5lakhs makes me feel that I should have started saving a few years earlier in life :D. The BTwin is definitely more affordable in comparison.
The way I am leaning towards right now is - get more 1st hand information about Btwin folding bike and if they are positive then I might go for it. If I will end up using it only for last mile connectivity of 2 to 5 km then I might be ok with it's drawbacks.
Meanwhile I will start a small investment to be able to buy a Brompton in a couple of years.
On a serious note, a 2nd hand Brompton might be the best bet, if I can find one - I lost a chance recently to get my hands on a 8 year old 2nd hand Brompton for around ₹30k!
In a somewhat related news, I heard from someone at Pro Cycles that Pune metro allows cycles in the last car (yes cycles, not just the folding ones!).
I am keen to find out if there are other affordable alternatives before considering moving to Pune :D.
Cheers!