How can you find out where the better technology is?

I'm sure there are many opinions about this.  My advice is that it's the people using the machines, more than the machines themselves, that matter most.  

You are looking for a place that seems well put together.  Is it easy to make an appointment, and is the appointment time honored?  Can you speak to some of the techs, perhaps?  You will see a lot more of the techs than you will of the radiation onc, and they are the ones actually administering the radiation, so it is good if you feel you can trust them.  Seek recommendations from people in your area, as well.

I chose a non-standard approach and I kind of had to be a good advocate to get it.  Ask what the center does to minimize damage to underlying tissues (heart, lungs, chest wall, bones).  Ask if you have any choices of approach. If you feel you get too superficial an answer to these questions, push a little harder.  A doctor should be reassuring, but the "there, there, don't worry your pretty little head about it" attitude belongs to the last century. 

And good luck.  Seems like you are taking a good approach to it! 

I live in an area with two top tier medical schools.  I also wanted more choices for radiation but there was very little NEW offered here.  My 3 left side tumors were right on my chest wall and the external beam people could not guarantee they would miss my heart and lungs.  They said they worked very hard at it, but no guarantee.  

 A lot of research led me to Arizona for brachytherapy, which is done internally through catheters.  They guaranteed to miss my heart and lungs.  Plus it only took 5 days of treatment - 8 days total in Scottsdale, AZ.  They have good verified statistics for 7 years, and the procedure originated in 1992.  External beam has 30 years of statistics.  It is my understanding that this technology is spreading, but not widely available yet.  I chose AZ because the practioners there have the most experience.  My insurance covered the treatment.  The travel is deductable.

My surgeon was not initially on board, so she called and spoke to the people in AZ.  She agreed it would work and was so impressed with my results that she is urging her big city hospital here to send a team there for training in breast brachytherapy.  (The AZ center trains most of the radiologists who do brachytherapy.)  It was horrible to be in that hot weather and it was no walk in the park, but I know I am not going to survive breast cancer only to die of a heart attack or have chronic lung problems. 

I would definitely find the place you like the best.  I didn't know then to ask questions or to ask for a second opinion.  Sure wish I had.  Even if you get started & change your mind.  You can always go somewhere else.  NJ