Correct, you need to use 'no quotes'.
Prior to 3.8.1, a bug in the code meant that using type 'text' would work for "now()", as we were automatically not adding quotes for values being used in pre-filters for date elements, even for type "text" (which really just means "add quotes to this value"). But that meant that (say) comparing a date with "EQUALS" and "0000-00-00 00:00:00" (to find null dates) was erroring out, as it gave "WHERE yourdate = 0000-00-00 00:00:00" with no quotes, which is a syntax error.
But of course fixing that now means that using NOW() with type "text" yields "WHERE yourdate > 'NOW()'", which doesn't work because it compares with the string 'NOW()' instead of the result of the function NOW().
So we now correctly handle date pre-filters, and only don't use quotes if you select "no quotes".
-- hugh