I have owned a LOT of bicycles over the years including four recumbents. I have built several bikes from the bare frame on up, including building wheels.

I live in San Francisco, and often have the need to use public transportation plus a bicycle, and I have been running into some restrictions on full sized bikes (FSB). For instance:

1) SF Muni doesn't allow FSBs inside buses, and they have a rack on the front of many buses that can carry only two bikes. The rack is pretty insecure, and there have been numerous thefts of bicycles off the front racks. The crackheads and bike thieves are pretty aggressive in San Francisco, likely because there is close to zero interest by the police in bike thefts.

2) SF Muni underground doesn't allow FSBs at ALL in the cars and there are no external racks.

3) Bay Area Rapid Transit (BART) has major restrictions on FSBs during rush hours, and they don't allow you to use the escalators while carrying an FSB. You have to hump it on your shoulder up and down two flights of stairs.

4) CalTrain has bike cars, but during major commute hours the cars often get full and you cannot board with an FSB. I have in the past had three trains stop at a station before there is room for a bike, and even then they stack them four deep and people don't take much care of others' bikes, so the bikes get all beat up.

5) Bike theft... if you leave it outside, no matter how you lock it, it may not be there when you return

A folder solves all these problems. You can carry them (folded) inside a Muni bus or underground car, you can carry them folded on BART any time, and you can carry them on the regular non-bike cars on Caltrain. Since you can fold it up and bring it inside, it isn't likely to be stolen while you are at work, either.

I went folder shopping at a shop in SF called Warm Planet Bikes, which also provides free bicycle parking for Caltrain bike commuters. It's a cool shop, selling only folders and utility bikes like Extracycles. They also do service and sell accessories.

I test rode a Dahon D7HG and liked it a lot right off the bat. I really liked the simplicity and low maintenance of the 7 speed Nexus hub, and for rides around the flatter areas of SF the gearing is fine. If I KNOW I am going to be doing a lot of climbing I will use my FS bike with its 27 speed drivetrain and 11/34 rear cassette.

What I don't like about the D7HG

1) cheap wheels with a very grabby seam that makes the front brake pulse like a mofo. I spent an hour or so this morning reworking it and it's now perfectly true and the rim seam is smooth. I put on some KoolStop MTB salmon/black pads in the front that I had laying around and that improved the front brake immensely. Still I ordered a set of Avid SD5 brakes for it.

2) Terrible, crappy pedals. I rode the bike a little over 20 miles yesterday (my first long-ish ride on it) and several times my feet almost slipped off the plastic surface, and I could feel the pedals flexing under my weight. I ordered a set of MKS FD-7 pedals this morning to cure that.

3) The saddle. It's OK, but I am a generally a hard leather saddle kind of guy (my other bike has a Brooks B17 and I have had Brooks saddles on most of my recent bikes except the 'bents). I ordered a Velo-Orange brown leather touring saddle with springs this morning. This bike has a pretty upright seating position and I think the springs will be an asset (pardon the pun). I love the Brooks saddles, but they are sure fond of themselves these days with their pricing. The VO gets great reviews, and it costs about 1/2 what the equivalent Brooks costs.

Other than that, I am pretty darn pleased with the bike. It felt a little strange at first, but yesterday after several miles I pretty much forgot about it being a folder and it felt pretty normal (well except for the beating you take on rough pavement with the 20" wheels). Overall, I am very very pleased!