I would. Here's the info from the 1.42 patch that's relevant:
IMPORTANT NOTICE FOR PEOPLE WHO INSTALLED PATCH 1.4
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The following comment only applies if you'll use savegames made with patch 1.4:
There was a problem in patch 1.4 with the regeneration of the inventories of traders. Because of this problem after some time the game crashes. Patch 1.42 fixes this but because of a technical issue it's impossible to totally upgrade savegames made with version 1.4. As a result, some magical items which are lying on the ground might lose their properties when applying patch 1.42.
This does not apply for items which are in the inventory of your party.
IMPORTANT NOTICE FOR PEOPLE WHO INSTALLED PATCH 1.41
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Savegames made with patch 1.41 and which were upgrades from savegames made with patch 1.4 have been corrupted by patch 1.41 due to a problem with the upgrade system. You should not use these savegames anymore as more than likely you will run into big problems later on in the game.
However, if you started afresh with a game made in 1.41, you will not observe any problems. The problems only appear for savegames made in version 1.4 that were upgraded to savegames made in version 1.41.