Quoted:
Are these practical or more of a competition only accessory? I am very reluctant to tweak my Glocks.
That's a whole big can of worms there! Comes down to how you use your Glocks how comfortable you are about modifying a Glock?
The biggest thing is, how do you release the slide on a loaded magazine? If you overhand or slingshot then you probably wouldn't gain much if anything from upgrading your slide release. On the other hand, If you do use the slide release, then I think it's almost mandatory to upgrade the slide release lever as the standard factory release is hard to manipulate especially if your hands are wet or sweaty.
I personally use the slide release method and have upgrades my Glocks with the factory extended slide release lever that comes standard on the G34/35's. I have been using it for years with no negative issues at all. Not sure what, if any advantages the Aro-tek version has over the factory ext. lever but it seems to me that the factory part is more low profile and hence a little more CCW friendly then the Aro-tek but having never seen of used the Aro-tek version in person, I really can't compare the two?
ETA: Here's a good thread to read all about the various pros and cons of the different slide release methods...
How often do you use the slide stop lever?