what keys would last the longest without that greasy look? I ask this because after a year all my das keys have that shinny greasy look and its really bothering me. They also need to be blank
IBM Model M followed by Topre.
IBM doesn't make keyboards anymore, and I'm not certain that they ever made ones with blank keys.
You
can get unprinted PBT keys for IBM from unicomp for like $20/set (super cheap). If you want to get a new keyboard from them with blank keys, I'm sure they will help you out.
PBT keys are very wear-resistant. The IBM/unicomp ones are a little more "rough" than (for example) the signature plastics PBT. I feel like it'd take them longer to smooth out, but I haven't verified this.
If you don't want a new keyboard, it's pretty easy to get blank PBT keys for your DAS.