A bit late, but I've used the SUM 1200 on two A1500+ builds using a Rii mechanical keyboard. They worked beautifully as did an old Corsair. iComp.de sell a Lyra 1200 that works well too
Hi and thanks for the info!
I was considering the SUM, but ended up with the Lyra 3. Glad to hear that it works well. Have not installed it yet, but it is on the to-do-list here.