I have only done that relative to buying mediums to have on hand. And at 2.5mo C has been in mediums for over a month already. But I'm not buying larges b/c I suspect it will be a while for that. The one thing that tempted me was a wool cover w/ some Irish thing embroidered on it (dh's family is nutty about being Irish)...but I held off. So yes I bought ahead to mediums. But I'm holding off on larges.