The Resilient Floor Covering Institute, a trade association that represents manufacturers of vinyl sheet-flooring and tiles, also puts the nix on osb. RFCI installation specifications recommend plywood as an underlayment material. Osb is acceptable as a subfloor material. Manufacturers have not seen a deluge of failures due to the use of osb under resilient flooring. However, they have received complaints of edge swelling that has telegraphed through their flooring products.
Manufactures feel more comfortable guaranteeing their products when they are installed over plywood.
All manufacturers of siding products I contacted agree that osb and plywood are equals. Kevin Chung, Engineer with Western Wood Products Association in Seattle assures us, There have been no problems reported from the field. Nail-holding and racking resistance are the same. Chung has noticed some concern about the use of osb among builders, but is quick to add, There is no reason for any concern. Both products serve equally well as a nailbase.