Thoughts of Pass XA30.5, 60.5

After having read numerous reviews & rave about XA30.5 versus 60.5, some would prefer a 30.5 over the doubling power 60.5, some would have contraditory point of view, believing higher power always having a merits of getting fuller sound, better soundstage or remarkable improvement of overall presentation.
But i just wondering why there is not much or none would like to try bi-amping two 30.5 to feed your speakers?! That maybe the way still processing the sweetness of 30.5, but never overdriven your speaker. Provided you're not using a full-range unit speaker with one pair of terminal on each side. A friend of mine has told me that should yield a unbelievable improvement over the pair of 60.5.
Firstly, your pair of speakers would be driven with more ease since each unit of 30.5 has just need to serve half of your speaker system.
Secondly, it would be more flexible & easy to sell one out if extra power is not needed anymore for getting an easy driven speaker at a later time. Your speaker wouldn't be over driven as well as receiving a bill of less electricity payment too.
More importantly, driving ability would be better than a pair of 60.5, so you could even have more choice of less sensitivity speakers.

But the drawbacks is, your preamp should possess two pairs of output, in addition you need an extra pair of interconnects & speaker cable.

Please share your comments. Thanks!