Should I use proper punctuation for single sentence alert/notification popups?

Question

Is it necessary to use a period for single sentence notification boxes? Even though its considered proper grammar to do so, it just looks ugly and feels too formal.

Here are two screenies for comparison (first includes period, second doesn't).

alt text http://wordofjohn.com/files/stack_alert_1.png

alt text http://wordofjohn.com/files/stack_alert_2.png

Answer 1

Can't go wrong with correct grammar

Answer 2

Good grammar shows to your customers that you took time to make a good software even where others might not took time.

This way they can expect the best out of you and your company.