We have 2 257B machines. You will never out do Caterpillar service, and you will never get better resale.
There is no harder soil we have worked in than this stuff here in Southern California. From abrasives like DG to expansible clays, or rock riddled silt, nothing harder. And, I have yet to get the machine to stall, or stop when digging. With the 6 way blade we can easily cut 4" from the top and not even break the tracks loose. If I had my way, the 257 would have a 287 engine, but, bigger engines are always better.
If the rumor is true, the merge of Cat and ASV is already taking place. It started about 19 months ago. I have not seen anything in my earnings reports as of yet, but it should not be long.