Glock .22 caliber conversion

[Teamless]

My boss, as previous thread (viewtopic.php?f=23&t=42720" onclick="window.open(this.href);return false;) stated is looking for a .22 caliber for his son to shoot.
His son can shoot my Glock 19, while it gets a bit heavy, he can do it for 50 or so rounds.

My boss likes the Glock and I got to thinking about the .22 caliber conversion kit.

Does anyone have experience with the conversion kit?
If so, good, bad, indifferent,
Pro's ?
Con's ?

Thanks