There seems to be a WIDE range of prices for 30rd mag springs. The following prices are directly from the manufacturers websites:
DSG Arms - $1.95 stainless steel
C Products LLC - $2.40
C Products LLC - $2.40 chrome silicon
Wolff - $7.99
ISMI - $10.25 chrome silicon
Obviously they use different materials but in the case of the C Products LLC chrome silicon spring vs the ISMI chrome silicon spring the ISMI costs over four times as much.
So here is my specific question:
On the six mags I keep loaded for home protection is it worth it to put in high dollar springs?

No, This is my opinion. I worked in the spring industry for 25 years and the chrome silicon spring, stainless steel spring we offer will more than take care of your need. There is no reason for what you want the spring for to pay more than $2.00 - $2.40 each. Again, only my opinion.

CP

I think the most expensive one I've seen is the Oly Arms ESpring...$15!  
Remember that springs wear from cycles of compression and depression, not from retaining a constant load. Springs can wear out, but with moderate use the springs are going to last a long time.  

i use wolff springs and they work great.

From their site:

A Few Reasons to use ISMI Gunsprings
 Certified Aerospace Specification Materials  
 ISO 9002 Quality Control Standards  
 All Springs are Heat Treated, Shot Peened & Stress Relieved  
 Proprietary Design Features Enhanced Durability
 12 Month Replacement Warranty  

This is apparently worth 10+ bucks a pop to someone. But too rich for me!