The Stella is not too challenging - you should be fine with that. The Maestro is the toughest of the whole range fwiw.
Mind you, I would have thought you might want to consider something slightly more resolving to really appreciate the magnificent Stella. The macs are great (used to own myself) but they hide a lot of information IMO. So it depends what you are ultimately after. The Stella will give you much bigger scale and sound staging with your existing amps - upgrade them to the 2301s would be magnificent.