I can't tell the difference between the 125 and the 130 string, but the Luxilon 4G is all I use now. I was a big string breaker, changing strings every couple days or once a week at least. Prince Problend was the only string that I could use for a while without breaking, but it gave me triceps tendon pain, and so I had to stop using it. Now I have to put a calendar event to remind myself to get my racket restrung once a month because these strings don't break. The tension keeps well for at least three or four weeks until there is a noticeable difference. The feel is way better than Problend ever was too, and at least as good as any of the more breakable strings I tried out over the course of a couple months. I use a Dunlop Biomimetic F3.0 Tour.
Very smooth feel, nice blend of power + touch. Seems to hold tension very well. My daughter switched to this string 2 months ago from Kirshbaum Pro Line II 17G. She says they have a more "solid" feel and that she feels the ball better. Her coach had to talk her into trying them, now she won't use anything else. She is a solid player, senior in HS (all state) and will play DII or DIII college tennis next fall. She uses a Wilson Juice Pro BLX, strung at 58 lbs.