They always have my size and stock and with my allergies/desire to not spend my time dusting, I can always count in them to get me what I need. Plus, they are 100x more affordable than store bought. If youre not using FilterBuy, your making a mistake.
I have purchased filters from this company previously and it has always gone well. I recently purchased next year's supply and both sizes arrived ahead of schedule. First rate company--highly recommended!