You'll get a mixture of replies both positive and negative. It depends on the individual.
For my part, I am approaching 2,000 hours and am enjoying it just as much as when I was at the 200 hours stage. If anything, I find it more enjoyable now, as I have more of an idea what I am doing than I did at 200 hours and am far more comfortable with my type. I flew a manually flown visual approach into a Spanish airport yesterday and it still gave me an ear to ear grin that took all day to wear off. These days I have passengers complimenting me on how nice the landing was rather than an instructor debriefing me on my myriad shortcomings.
However, I know guys I trained with who were moaning about doing circuits at 50 hours and were claiming to be "bored" doing cross country exercises at 100 hours. I bet they are those people who say the job isn't what they thought it would be.