Yes, you would be better off using an if statement that specifies that the value needs to be over 0. The same type of thing is used on the "Save X%" in the customer/main/product.tpl.
Here's one way to show the list price if there is one (XC's default is $0.00):
Code:
{if $product.list_price gt 0}
<TR><TD class="ProductPriceConverting" valign="top">{$lng.lbl_list_price}:</TD>
<TD valign="top">
<FONT class="MarketPrice">{include file="currency.tpl" value=$product.list_price}</FONT>
</TD>
</TR>
{/if}
Just put it above or below the standard price. It may also work elsewhere.
- Mike