I'd be testing a selection of Crumpler bags out on a multi-day trip to the west coast. As per my travel methodology I honed in on the two-wheeled carry-ons in Crumpler's vast product line-up, and two models came to the forefront: The Dry Red No. 3 carry-on and the Spring Peeper with Wheels. (Crumpler's nomenclature is quirky, to say the least.)

The Dry Red No. 3 was the closest thing I could find to a standard box-shaped rolling carry-on with a retractable handle, though its tapered shape suggested it was sacrificing a bit of carrying space for style. I wasn't sure it would efficiently max out my carry-on allowance for the longer trips I mentioned in the "How I Travel" post. (Thankfully I was proven wrong.)

The Spring Peeper with Wheels, in contrast, is a duffel bag, albeit a wheeled one with a retractable handle; while it is still within the constraints of a carry-on size, its 40-liter capacity (versus the No. 3's 27-liter storage space) promised to swallow anything I'd need to bring.

As a reviewer I had the luxury of borrowing whatever bags I wanted, rather than agonizing over which to select. I chose them both for a side-by-side comparison, though I would only be bringing one on the actual trip.

I'll start with the Dry Red No. 3 and some of its design features. First off, the top handle is integrated into the design of the bag itself, not a discrete piece:

It's nice and chunky to grab, and though you can't see it in the photo, the bottom is lined with comfortable neoprene. The way it's integrated means there's no worries it's ever going to break off.

At the bottom of the bag is a little plastic lip. This provides a nice grab point, for when you have to hoist it onto the conveyor belt; you can grab the lip with one hand and the top handle with the other.

The zipper pulls are nice and chunky, and of course come with rings for a travel padlock.

I like the little detail of the inside zipper for the top flap being bright red, so you can easily see where it is and don't have to feel around for it.

Okay, now it's time to pack. (I did this in real time prior to the trip, so apologies for the cell phone photography.)

I needed to pack for a three-day trip. First I laid out everything I'd need to put in the rolling carry-on, and not in the secondary bag I carry aboard a plane. (The laptop backpack review will come later.) Here we see what I need to bring:

From left to right:

Electronics: Camera (Canon G9, my go-to travel camera as it takes far less space than an SLR), audio recorder, assorted cables and chargers for these and a laptop, though the laptop itself goes in a different bag as per my habits touched on in the previous post.

Clothing: One pair of backup jeans in case I have a coffee disaster; three each of T-shirts, boxers, and pairs of socks (one for each day).

Toiletries: Electric toothbrush, a TSA-friendly 30 grams of toothpaste in a plastic Muji tube.

That's it. As you can see, I roll my clothes--a space-efficiency habit from my backpacking days--and I really do try to travel as light as possible.

The electronics go into the pouches on the "top" (from this perspective) walls of the interior:

The toiletries go into a Ziploc on the bottom pouch:

Everything else fits easily into the Dry Red No. 3, with space to spare:

You can't quite tell from the angle, but there's still about two inches of clearance remaining in the bag. If the trip was seven days and I needed to double up on the clothing, it would be no problem. I'd zip up the bag and call it a day.

However: I'm traveling to San Francisco, a city notorious for unpredictable weather changes. In the Bay Area, go outside with nothing but a T-shirt and you'll soon wish you'd brought a jacket; go out in a jacket and you'll soon have a reason to strip it off.

I check San Francisco's weather forecast for the days I'll be there, and they're saying rain--potentially heavy--and chilly mornings and evenings. If it was one of those trips where I'm going from hotel to conference center and never exposed to the elements, I wouldn't change a thing; but due to some things I have to accomplish on this trip, it's not clear how long I'll have to be outside for. So now I have to pack for rain and cold. This requires adding just four more things:

Water-resistant boots, an umbrella, a hoodie and a rain jacket. The boots and the hoodie are luggage-killers as they swallow a lot of space. You can mitigate this slightly by stuffing socks and electronics into the boots, but I want to see what will fit naturally.

I shuffle some things around and get the boots, wrapped in white plastic, in the left side of the bag (which will be the bottom when the bag is upright). I pack the original contents around that and throw in the umbrella, wrapped in blue plastic. So far so good.

The problem is the hoodie and the rain jacket. If wedged into the main compartment or the interior flap, they're simply too bulky to comfortably get the bag closed.

However, the No. 3 has a nice feature--the flap also features a large external compartment, with a gusseted design that allows it to swallow bulky goods by expanding outwards when full.

This compartment cleanly fits the hoodie and rain jacket.

This extra strip of material, concealed when the bag is not fully loaded, provides a few extra inches of depth.

Compression straps at two corners help you render the bulk a bit sleeker.

There's also a nicely chunky handle on the side, another way to hoist it up onto the conveyor belt.

Now it's good to go.

Conclusion on the Dry Red No. 3: I'd say it's perfect for a short-term trip (3-7 days), provided you travel with a similar amount or slightly more than what I typically travel with, as seen in the first few photos. Although it's difficult to tell in 2D photos, there was still plenty of room in in the bag for additional toiletries or cosmetics, for the metrosexuals and make-up-wearing women among you.

The fit and finish of the bag appear to be quite good, but I would not get to experience those things on the road. For that stay tuned for the Spring Peeper review, up next.