I've been looking at the Marshall 1960AX to pair up with an SLO-100 head.

Will that sound any good? If not some cabinet recommendations would be greatly appreciated. I mostly play alt/hard rock (muse, radiohead, crush 40).


That seems like the obvious answer, but I've heard pretty bad things about them. What are the reasons I would choose the Soldano cab?
Meh, it's all going to come down to personal preference.  Best option is for you to contact your local music store and see if you can bring your Soldano in and test it out with the cabs in stock.  See what works best to your ear.  

I'd personally go with a Mesa Traditional Slant 4x12 loaded with Vintage 30 speakers. That's if I had to pick a 4x12 to go with a SLO.
Gear: Gibson Les Paul Studio, Gibson SG Special, Fender Stratocaster, Fender Telecaster, Fender Jazzmaster, Gretsch Pro Jet, Carvin C350, Epiphone ES-339 P90, Epiphone ES-335 Pro. Peavey 6505, Sovtek MIG-100, Vox AC30, Peavey XXX.