It depends on what you are looking for. The Glendales get the more traditional tele tone. The Callaham offers a little more weight and sustain. I like the Glendale cold rolled steel with steel saddles myself.
I find that Teles that set up low like a Callaham, those that naturally set up high (Baja) like a Glendale. Guys with low output pickups, with a twangier style like Glendale. Guys playing with more gain and who have issues with squeal like Callaham. Guys with seriously offset string sets like Glendale, Guys playing lighter guages like Callaham. Guys who like the idea of an aluminum E-A saddle (nice!) like Glendale, those who want to completely cover a stock production bridge pup rout (and avoid "Butt Crack") like Callaham.
And others violate every single above generalization. If you consider Joe Barden, beware those saddle height screws are very high and they will cut you up. But replace all the hardware with 6-32 (tap out the bores) of the correct height - not bad at all IF you like really strong nickel color plating.
Confused? Sorry. Try the search function and you will see I've only scratched the surface.
This is an older Callaham flat plate for vintage mounting / specs, with a set of 70's Stars keyhole saddles that have so radically transformed this guitar. It has the snap and twang - but as Boris pointed out works well for higher gain applications....I too was ready ready to drop the $$$ on a sweet Glendale or Callaham vintage style setup but the set of saddles I already had saved a ton of money and sounds / works killer
The Tele I'm upgrading is a MIM Nashville with an ash body and a maple neck. Nice blonde translucent finish. It's not a feather-weight; I'd say about average. I'm thinking of moving it somewhat in the direction of being a poor man's 50's Tele. I was going to start with the bridge and saddles.
I have installed a Callaham replacement bridge and saddles on another Tele and it worked out quite well. It was their Enhanced Vintage kit with the new style of compensated brass saddles. That guitar now sounds bolder with better sustain, highs are tamed just a bit. The intonation is very good. Overall I'm quite pleased.
Just curious about Glendale. Callaham's bridge plate is beautifully made, though somewhat thicker than a normal vintage type. Glendale might be the way to go with the other Tele.