Admittedly, gear is a personal fit so this review might not be useful for everyone.
The helmet: Airoh S4
I bought this helmet just before the trip, about $250 including shipping from the UK. My previous lid was a Shoei Multitech. I thought about bringing the Shoei, especially since the flip-up face would make conversation in foreign languages easier. However, its weight makes my neck sore on long trips and I would need to remove the Autocom rig. So I decided to try something new.
I love the S4. It's almost a pound lighter than the Shoei and you can feel it the moment you pick it up. The ventilation is stellar; this didn't thrill me in the sub-zero Arizona weather but has been a blessing in southern Mexico. The sunshade is a liability at 80mph but helpful on sunny days. I have no trouble wearing the helmet with glasses or earbuds.
One of the best features of the S4 is the Euro-style clasp on the chin strap. I don't understand why every helmet in the US is not sold with this clasp - fast and super easy to work with gloved hands.
The jacket: BMW Rallye 2 Pro
I really didn't want to like this jacket. I already owned four motorcycle jackets but somehow none of them were suitable for a long trip in multiple seasons. I tried on pretty much every possible jacket in Cycle Gear, Scuderia, and the Dianese store... but nothing came close to the BMW. Unfortunately nothing came close to its $700 price tag either.
What I love about the jacket:
* Vents, vents, vents! It has chest vents, arm vents (down the whole arm), side vents, and back vents. With the liner out I've been perfectly comfortable riding on the hot Oaxacan coast; with the liner in (and a heated vest) I survived subzero temperatures in Arizona. The closest competitor is the clone Revvit Cheyenne, which still has two less vents.
* The armor is very complete yet very comfortable. I like the way the arm pieces reach all the way to my wrist and the elbow piece cups pretty far around the sides of my elbow. The back protector reaches down nearly to my tailbone. I feel very secure.
* Lots of pockets. One of the chest pockets is goretex-lined and has a water-resistant zipper, perfect for a cellphone.
* The fit is slim. Most synthetic jackets are very poofy on me, which (aside from aesthetic issues) makes me concerned the armor won't stay put in a crash. I like my armor to feel like a part of me rather than something I'm inside.
* The armor (and thus most of the weight) zips out in one convenient piece. The idea is to make the jacket suitable for normal daily wear if I'm not riding. So far the only places I've holed-up long enough to consider this have been places I didn't need a jacket, so this hasn't yet been an issue.
What I don't like about the jacket:
* It has a pocket for a cameback bottle, but the necessary routing path is longer than the standard cameback hose. I don't particularly need to drink water heated to body temperature so it's a minor nit; I don't use the feature.
I wear the jacket with a long-sleeved baselayer at all times, even when it's blistering hot. The synthetic pulls the sweat off my skin so the jacket doesn't feel like a sweatlodge, even if I'm not moving.
The pants: BMW Rallye 2 Pro
I really, really wanted to resist. I especially didn't want to look like the BMW factory race team with a matching suit but... like the jacket, the pants are significantly better than anything else I tried on. They're vented. The armor nicely wraps around the sides of my knees rather than just the front. They're comfortable both with and without the liner - I can walk around town in them. Unfortunately they're twice as expensive as the alternatives, about $500. I'm going to be living in these for six months so I splurged.
Like the jacket, I wear a baselayer under the pants at all times.
The boots: Aplinestars Web Gore-Tex Boot
They're comfortable and they're waterproof. I have only these and a pair of sandals to wear on my feet for six months, so fancy MX boots were out of the question. I bought the Apinestars on sale at Cycle Gear at the beginning of this last summer for around $150. They're holding up pretty well to my continual abuse.
The gloves: BMW ProSummer, Racer Mesh Glove
I bought a $140 pair of fancy Dianese race gloves at the beginning of summer. They didn't survive a single riding season before they developed holes in the palms. I can't say that I'm overwhelmed with the quality my expensive Dianese leather race jacket either - a single low-speed slide wore a hole in the forearm. I've sworn off Dianese leather.
The BMW is a midweight goretex-lined waterproof glove; I have heated grips so I don't need gauntlets. The fit and build quality are excellent for a surprisingly inexpensive glove ($100). However, they haven't seen a lot of use since I switched to the mesh gloves when I crossed into southern Baja. The Racer gloves were a bargain at $60 and have been great in hot temperatures since my hands tend to sweat in heat. Plus they're orange!
I got pretty lucky. Almost all of my gear was new when I started and there wasn't time to do trial rides, so I could have had a variety of fit problems. However, everything is working out pretty much as-advertised. The one disappointment has been, oddly enough, my underpants.
I bought four pair of synthetic underpants of the type you can wash in a sink and they're dry by morning. I've since found that laundry service is ubiquitous and the polypropylene material irritates the skin of my, ummm... inner thighs. Needless to say, I have since acquired cotton underwear!