been looking for one ourselves, luckily have found couple of owners of 2510's locally, and these are their experiences. the shoes that run against opening disc on the early ones were adjusted with a bolt, the later ones used a spring to hold them tight, you want the spring. make sure the notched closing disc isn't wore out, it will drag trash if it is.       in high residue they look like they close good enough if you have the longer closing arms that put the closing system further back.        pre plant nh3 is kinda risky with it because it doesn't put the n very deep, and seed burn is a risk.     they appear to be a  high maintenance machine