I use leather saddles on most of my bikes, predominately Brooks, but I also have Wright's and Ideale. I heavily treat the underside with Proofide at least once a year and keep the tops covered if they are exposed to weather. FWIW most of my bikes have fenders which I am sure helps. For saddle covers I use free shower caps from hotels, plastic shopping bags (Target's are the best) and I actually have a couple of honest to god Brooks saddle covers, probably because they came with the saddle.
My bikes get ridden in any weather at any time regardless.
Aaron
