simply put, the G17 IS easier to shoot than the G22. But only within the context of feel. The fact is, they are both Glocks, and thus handle the exact same EXCEPT with regards to the effect of recoil. This is because, the G22, being a .40 cal operates at a much higher pressure than the 9mm.
I have found shooting a G22 to not be the most enjoyable experience. I am not saying that i can't shoot it, but rather that it is just not as comfortable to shoot as the G17. The gun seems to vibrate in my hands as the recoil dissipates through the frame.
I believe it has to do with the polymer frame, and its inability to absorb the recoil caused by the immense pressure of the .40cal round.
I know others who have shot the G22 have said the same thing.
That being said, a .40cal round out of a metal framed gun, such as a Sig P226 shoots remarkably well. The heavy weight of the metal frame absorbs the recoil of the .40cal extremely well.
again, i would recommend you try one before you buy one. I don't know where you are located, but if it is in the GTA region, you can swing by target sports and shoot one of their G22s on the range and one of their G17s and make an informed opinion.
If you want a comfortable .40 cal handgun, get a metal framed one. That's just my opinion.