The 'blender system' implies the use of a mic and a pick-up, and the sound is blended between the two, bu you, the plicker - that is it is a setting on the guitar. The pick-up gives you a strong clean signal, with little noise and less feedback problem - the mic gives you a more natural sound, but can introduce some noise or feedback. The blenders typically require more wood work 'surgery' in that some place a modest sized electronics control panel in the rim of the guitar, and the under saddle pick-up requires the woodwork explained by Whistle Stop above.

If you are unwilling to have the saddle worked on, but you still ike the idea of using a mic and a pick-up then the Fishman Rare Earth blender is a great choice. Frankly, I suspect it's a great choice anyway. No cutting, except for reboring for a larger end pin.

But I must say, I am not convinced that a blender is important. The Rare Earth has an excellent sound by itself, though it is a bit 'electric' sounding, as any pick-up will be. If you wish to blend, a mic on a stand can always be used which gives you additional flexibility because you can move close, move away, as you wish to affect the mic's signal.

I like the idea of the blender pick-ups; I just can't help remembering why I use a pick-up instead of a mic in the first place. I typically deal with a wide variety of sound stage settings. Different rooms, different stage sets, instrument mics almost require a sound man working the mixer - and some experience at coping with the problems mics introduce; levels, feedback, placement, EQ, overall balance. Pick-ups greatly reduce those complexities.