I'm currently on a survey job using an R44 & we conduct 100 to 120 landings/day (about 12 hours), in very confined areas many of which require max power (& sometimes a bit more!!)to get out of. The machines appear to be coping ok after nearly 6 months of this type of operation, & with 15000 landings left to go before the end of this round we should have a good idea how they go. When operating close to the envelope edge of "High, Hot & Heavy" they require your undivided attention, but generally handle the hard work well. Most problems we've encountered are with the Lycoming rather than the Robinson side of the product, though the requirement to keep paint on the rotor blade seam is proving costly while working in the dust. I could be wrong, but I don't think any other helicopter needs the blade leading edge painted every 100hrs!! This wouldn't be as big an issue in Ag work as the landing site can be chosen with more consideration to dust, as opposed to landing where the GPS tells you too like we do.
Having flown a B47 & done Ag work in a H12E, I tend to agree with other posters that performance wise (not lifting capacity) the R44 is the best piston available today, but a "Utility" model with a few hardpoints to bolt all of our toys to would be helpful. We always want more power, but the same engine developing 305HP in a H12E was notorious for dropping valves, so less power traded for reliability is something I'll learn to live with.
Somehow I don't think this quite matchs Franks' vision of airport to country estate & return transfer flying.