Since I've spent hours and hours researching and at least 2 hours test driving a Toolcat, I can tell you that comparing a UTV to a Toolcat would be more like comparing an El Camino to a tri-axle dump truck. They are similar in that they haul things, but the (gonna make up a word here) heavydutyness is huge. A Kubota RTV1100 is a pretty heavy duty UTV, the strongest in my opinion, but it isn't even close to being in the same class of 'heavydutyness' as the Toolcat. Again, this is just my opinion, but I'd say that there is far more difference between an RTV1100 and a Toolcat than there is between an RTV1100 and a Yamaha Rhino. The Rhino is a dang sturdy vehicle that has a bed and can haul a load but you'd ruin a good Rhino using it for work like you could an RTV1100.
Again, no disrespect intended towards any unit I mentioned, I just wanted to point out that the Toolcat is considerably different than a UTV.