Great speaker and pretty light too. I got one a couple months ago and put it in a Dr Z 1x12 Convertible cabinet. I've played it on a number of gigs with Axe-FX using the MAZ 38 model and also with a Dr Z Therapy. I've played it mostly with my Suhr Tele, Gibson CS-336, and also at home with my Anderson Strat.
The speaker sounds really sweet and clear. It has plenty of low end, but not too muddy. Plenty of high end for me as well, but it does compress which I guess is the alnico character. It's my first alnico speaker, but I can definitely feel the compression.
It is a beautiful and sweet sounding speaker, but it doesn't have a fast or percussive attack. I kind of miss that a little bit so there is a tradeoff there. I play low gain clean to a little breakup and maybe some light OD in front, so I'm definitely on that side of the spectrum.
I haven't made any IRs of the speaker. I've been using a patch that has an IR of a Celestion Alnico Blue (I think the factory one but can't remember for sure) for output 1 to FOH and my monitor, and then sending output 2 (without cab sim) to matrix GT-800 then to the Dr Z 1x12 Cab. It's been really fun working that way so far!