I really like Dana's response - it covers the primary consideration - how much time would it REALLY take to write unique Meta descriptions? If the TRUE answer is "unrealistically too much time", then a template COULD work. The trick though is addressing the issues Dana talks about.

If you only use a primary product name as the variable, you run risks. If you have a 2nd database field you have that includes some differentiation between otherwise identical products, that can help.  As long as you understand total length as a consideration.