I tried a few recently. I use Big Apples 2.35″ on my Fargo and the front of my 69er Hack Bike as i find them better than anything else out there for comfort (and surprisingly fast). I have also managed to bodge my full length mudguards around them as well – although the tolerance is close to say the least!
I tried a 29×2.0″ Big Apple folding (from CRC for £25) but it is nothing like the volume of the 2.35″ (i’d say around 50%) so wasn’t what i was after (and not 2″ wide either). I also ordered a Continental sport something or other in the biggest size i could get (700x52c non folding) but in reality it was 47mm at best and was disappointing again from a volume point of view. Both have been used for less than 5 miles and i’d happily offload them both for £20+ postage if you want them as they are just sat redundant in my garage?
I also have a set of Specialized Borough CX in 700x42c which are pretty good (especially as i got them for £4 each in the Edinburgh bike shop sale a year or two back!) and i think they can be had in a slightly larger size?
Edit: Damn my slow typing. As above then really!