I had the same problem with the stock boots running close to max angle with bus CVs. What happens is the axle rides the inside of the boot where it is rolled into the steel part and pinches off the rubber, then you got what is in the first picture.
I went to the two piece boots shown in the second picture and they lasted much longer but would still eventually wear through and tear at the very first bellows. The same thing happens, the axle rides the rubber continuously because of angle and it wears thin then tears rather than pinching out like on a stock boot. They will last a good long time but you will be replacing the rubber part ocassionally, maybe once a year if you ride a lot. Running less angle helps (SCREW that, right?)
One thing I found out is that the zip ties they send with the boot to hold the larger end to the flange doesn't work. You will want to use stainless safety wire wrapped around the rubber just inside the lip of the flange. Twist it up just tight enough so it doesn't cut the rubber and be careful not to get it caught up under the CV bolts as you tighten them down.
I run 930s now with the same type of boot. Haven't had to repalce one yet! (a boot that is, come to think of it, joint neither!
)
Good Luck,
Dale