I finished my IR a little over 5 years ago. I have since managed to blag my way into the LHS of a jet, am earning a tidy salary and can count on my fingers the number of days at work I haven't enjoyed. As you can imagine, I feel pretty happy with my lot. However, a lot of the guys I know in a similar situation are really pissed off and are desperate to move on.
I think nearly all still enjoy the thrill of flying, but I do feel that many had unrealistic expectations of the job. Your life is held to ransom by the crewing department, you will need to get out of bed at an ungodly hour for weeks on end, you may need to commute to the other end of the country for work, you will be busiest during summer and will be heading off to work just as all your mates are off to the pub / barbeque on that summer bank holiday weekend, and you always have in the back of your mind that if your employer folds, you may have to emigrate to China / Middle East / India to stay in work.
There are a huge number of downsides to the job, but all the above are things people told me to know and accept before I even thought about training. Personally, like most of the guys & girls I fly with, the first sector of the day is spent bitching and slagging off management, but its all rather superficial - on balance, its still the best job in the world, by a long, long way.