I've had a Tumi widebody for a few years now, and am 100% satisfied with the dimensions. It gets used weekly around the EU and EU to Latin America, so a mixture of small airbus and EMB's in LatAm (Taca, Copa, Lan); the usual suspects over the Atlantic (on BA, IB, AF, LH, LAN).
Some issues from time to time (Taca mainly), but always relating to the weight of the bag (I hate checking bags and will tend to do 2-3 weeks with this thing as carry-on) - I think the wider format makes it look bigger than other bags so people ask to check the weight, but once I get past that, it fits nicely in the overheads.
On some EMBs it has to go on the DEF side of the plane or get checked at the gate; on 767s (LAN, Delta) and some of the larger airbus (IB, AF) it has to go sideways into the overhead rather than wheels in, and I tend to carry along the aisle so as not to snag along the way.
I had a 22" Travelpro (standard width), which I found just too long and tough to pack shoes into (UK size 12) along with everything else. That got loaned to a friend, never to be seen again, and I picked up the Tumi in Heathrow after giving the shop assistant a very hard time to check that it would indeed fit in the carry-on sizing frame...
RP