"I am a huge fan of Adagio's infuser cups~ they're made of a Borosilicate type glass, which retains heat longer than a typical tea mug, and isn't as prone to breaking from thermal shock (like washing your cup with hot water, then pouring cold water in it & having it crack). It's a very thin glass as well, that looks incredilbly delicate but actually is fairly tough~ you should still handle it gingerly, but it won't break as easily as you would think.
I have a weird quirk about thin glass too~ i swear tea & coffee tastes better out of it. I'm constantly scouring the stores, but never find any, so I've resigned myself to buying them online & risking the bouncing dangers of shipping it~ more than once they've arrived broken or cracked; but never have Adagio's, so you can buy it with confidence from them.
I also love this particular shape of mug- the barista special wide mouth. There's just something charming about it. I had recently ordered their other infuser mug, the traditionally shaped one; loved it, and was about to order a back up one when this caught my eye. Immidietly i ordered it, and was super excited, but when it arrived i realized with some dissapointment that the glass lid only fits over the infuser; not the actual mug.
The caveat being, these cups, due to their shape, will lose their heat faster than a regular shaped one~ even with the Borosilicate glass. It's just the nature of physics; not a design flaw~ whether Adagio intended their lids to be used after steeping, I'm not certain, but their traditionally shaped mug's lid fits once the infuser is removed, and I assumed this one would too~ which would compensate for the jumbo mug shape's inability to retain heat. It may seem silly; but i drink tea all day long; and I drink it fairly fast; & having used this shape of mug in the past, i know it will entail multiple trips to the microwave to warm it up if I want it to stay hot.
Aside from the lid debacle, the mug itself is great~ it comes with a glass saucer; always nice for serving & avoiding steam rings on the table. The mug is well made; the infuser is made with the same soft mesh the traditional shaped mug's is; which helps avoid knocking of the two, and in turn, helps avoid chipping. Adagio's infusers are always outstanding and allow for very little to slip through, if at all~ I purchased a competitior's mug a few months back, whose infuser was made out of the same type of glass the mug was, and it had 4 nearly invisible slits at the bottom for the water to steep through. those slits were so microscopic I thought for sure nothing would escape them, but I ended up with far more sediment in my tea using that than I do with Adagio's.
It also begs to be said that the wider shape of the mug lends itself a wider infuser, which allows the tea leaves more room to expand & steep; and therefor, can provide a better tasting cup of tea in theory.
So- my advice: great mug, and if you don't mind not having a lid, than buy it. If you prefer having the lid, or don't want to reheat it several times in the microwave 9which I personally always think kind of leeches some of the flavour out) stick with their traditionally shaped one. It really just comes down to a matter of aethetic preference, and the proximity of your couch, a good book, and the microwave."
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