I'm very highly biased. I'm a delighted 2006 Trek Portland owner. I've also been car-free since April 1999.
The Portland isn't what springs first to most people's minds when thinking of an ideal bike for a car-free rider. And, it probably isn't. But, for those of us who prefer our car-free bikes with drop bars and a bit of spunk, it's damned near perfection.
The Portland doesn't slot into any particular cycling pigeonhole, so it's a hard bike to sell. This makes it tough to find at even the largest, most well-stocked Trek dealerships. IMHO, it's worth seeking out.
The Portland isn't a roadie's road bike. It's 24 pounds (56cm), with much of the excess in the wheels due to the disc brakes. It's not a cyclocross bike. It has a triple and disc brakes. It's not a touring bike. It's not steel, the carbon fork won't carry a rack, and the front geometry is too quick.
These things make it an excellent all-rounder, and as a car-free cyclist, that's exactly what I need--a bike that's maybe not 100% at any one thing, but is 95% at everything.
I like the disc brakes in the rain and snow. I like the triple when on the climb from the grocery store. I like the way the carbon fork takes the sting out of broken city pavement.
I like that the cyclocross-style front end keeps handling pretty quick, yet it's not twitchy on descents. The neutral front-end handling keeps the bike pointed where I want it even if I sneeze, yet makes it easy to flick around potholes, even when they appear in the middle of carving a corner.
I like the touring bike style rear end geometry. It keeps the bike stable and comfortable on the bumps. When loaded with all my commuting gear and a week's worth of groceries, I hardly know the load is there. The bike remains stable, is never tippy, and it pulls away from stoplights just as nice as when it's unloaded.
Yet, join a fast group ride and there's nothing about the Portland that keeps it from taking its pull at the front, or dropping poseurs on carbon wonderbikes. It seems to take special glee when unshackled from its everyday load and running with the pack.
My only beef with the bike are the stock wheels--and even then, only the rear one. In fact, I never had a problem with the front wheel. The low-spoke-count wheels with their paired-spoke lacing sure are pretty. And they're probably perfectly adequate for ordinary commuting and riding.
Clydesdales and car-free people seem to have real difficulty with them. I'm no clyde, but I stress the rear wheel in particular on every grocery run. As a result, it was frequently out-of-true and broke spokes with frustrating regularity--despite two complete rebuilds and a total warranty replacement from Trek. I got only 8,000 miles out of them before I just couldn't get rid of them fast enough.
The solution is a traditional, 32-spoke, 3-cross rear wheel. The Portland's 130mm road bike spacing in the rear makes it hard to find disc brake hubs. I found--and am happy with--the 32-spoke rear disk 130mm road hub from Velocity ($140). My Portland's new wheelset uses that hub with Velocity's VXC disc-specific hoop, held together with double-butted spokes. You could get by with the stock 24-spoke wheel in the front, and just upgrade the rear. But I also wanted a dynamo lighting setup, so I got new wheels at both ends.
The new wheelset has made my Portland into the bike it was meant to be--a bulletproof reliable city commuting speedster that can also haul home insane amounts of groceries. And it still takes pleasure in showing poseurs its rear fender and lovely dynamo taillight.
My Portland, with its new wheelset, it's winter fenders (45mm PlanetBike Cascadia) and studded snow tires, (35mm Nokian Hakkapeliitta W106). In the three-seasons, it wears 28mm road tires and 35mm SKS P-35 fenders.
BTW, especially in a car-free situation, I recommend a rear rack with dual siderails. It's a whole lot easier to mount a trunk bag on top and hang panniers at the same time when they have their own mounting rails.