I have had my tanks for a couple months now, they aren't quite as soft as my SST8's were by time I had to throw them away but they are close. The extra stitching and such at the toe portion of the shoe has it a lot sturdier, and to some it may feel stiff, to me it feels really good. The shoes definitely run a little narrow, but to me and my non wide feet they feel good.
Definitely try a pair on first, but they do break in a bit and for me they feel a lot better than the SST8's and spending a full day bowling my feet feel better with these than they ever did wearing the 8's.
And just one small thing to consider, Dexter has teased SST9's coming fairly soon.