I'm not sure that the Kailh switches in Tesoro Gram Spectrum are exactly the same as PG1280. From Kailh's product images of the switch (http://www.kailh.com/img/gs44.jpg), it has a different type of clips on the sides.
The image they use could be of a prototype though and not the final product. They look very close otherwise.
Edit: Tesoro's renders from pre-production press does match the renders of the PG1280.
The stated actuation point does differ however. An old figure for the PG1280 is 1.8mm, where as the Agile is rated to actuate at 1.5mm.
I wonder what changed: the PG1280 or which model to rebrand as "Tesoro Agile"?
delicious KaleShow Image(https://vignette2.wikia.nocookie.net/dragonball/images/f/fe/Screenshot_2017-06-03-22-47-36.png/revision/latest?cb=20170604030200)
IMHO Kailh Speed stems are better in Cherry MX housings. Presumably not speed anymore, but the normal actuation distance works better, and everything else feels/sounds better, plus it's compatible with damping clips. I really like copper stem in vintage MX Black switch.The sliders do feel better in MX Housing! Especially in retooled MX Black housing.