A huge money saver if you're handy enough to get used Silhouette glasses on ebay for $25 instead of shelling $250 for frames...
Absolutely a huge money saver.  Used Silhouette glasses (frames+lenses) on ebay are circa 25 bucks, new Silhouette frames are circa 250 bucks - so every time I get new lenses now, or a frame breaks, I save $225.  I've replaced frames or parts of frames now like 5 or 6 times, by buying used Silhouette glasses on ebay, tossing the lenses, and using these tools to do the work myself.
Rating: 5 stars