Honestly, it's a bit silly to think that any of the major diabolo models aren't great for "numbers". Have a look at some videos. Think about what people are doing with the various brands. There are people out there doing 4 diabolos with each of the main models because they prefer that model for numbers.
So, how a Sundia Sun is "too slippery" (really, I have no idea where that thought comes from), or a Taibolo is "designed for multiple diabolo use", I have no idea.
They're all stable. The difference in spin time isn't usually noticeable. I'd be hard-pressed to accurately rank them for spin time. What is true is that they all have a slightly different feel. Some are a bit narrower. Some are a bit lighter. They all look different. Some feel a bit softer on the string. This is all personal preference and the differences are subtle. If you think choosing any one of these main brand models over another is going to affect your learning then you're mistaken.