I have two Surface Pro 3's, the i3 and the i5 and both run Cakewalk by Bandlab beautifully!
People around here are always throwing huge amounts of RAM around as necessary but the truth is I've never made a Sonar project that used more than 1.5GB of RAM, that includes HUGE ones with 100 track, Addictive Drums, Garritan Personal Orchestra, Lounge Lizard, Trilogy and endless audio tracks. My Surfaces have 4GB and are snappy; when I upgraded my main machine from 8GB to 16Gb it made zero difference. Mind you, I do know that if you're running enormous sample libraries a lot of ram CAN help, but in my opinion for 99.5% of all people even 4GB is enough. Real world comparison: my Dell XPS 13 has 8GB and the same CPU as the i5 Surface, there's zero difference in running any Cakewalk project I have tried.
R