OK...I've been in and around LOTS of SUVs over the years. I myself drive a 2001 Toyota RAV4. Wimpy? HAH! Only if you get the lethargic automatic version. My 5-speed model is quite zippy, actually, and gets decent gas mileage for being a 4WD (22 city/27 hwy). And it's had zero problems, with over 15,000 miles so far. With Toyota's reputation for quality and reliability, I would expect nothing less. The base price is a bit high for what you get, in terms of equipment (around $22K), but I feel it has good value per dollar overall.
That said, it sounds like your brother is looking for something a bit bigger, in terms of capacity and size. Personally, I like the mini-SUV because it does most of what the larger ones do, but without the bad fuel economy. Sounds like Nissan Xterra, Toyota 4Runner (wait for 2003; they are being redesigned), Honda Pilot, Chevy Blazer, Ford Explorer, Jeep Grand Cherokee, etc. would be the most likely candidates for him.
Most people I know of who have Explorers rave about them. I drove a '96 Explorer Sport a few times (I detailed it for the owner). It was a great vehicle, extremely roomy, comfortable, and easy to drive. It also had quite good power with the V-6, and the owner loved it. The Jeep Grand Cherokee...that's a pretty expensive alternative. I'd say they aren't quite as rugged as the Explorer, as they are more of a luxury vehicle like the Acura MDX or Lexus RX300. They can tow pretty hefty loads, though, and have unbeatable drivetrains. Pretty tough underneath the glitz.
It would pay for your brother to make a list of what he's looking for, and match it with vehicles that suit him accordingly. Once he narrows it down to three or four, time to go test-driving. That's the fun part.