I my opinion, this is a big bug by MS in SSIS. There is a very simple effective workaround that works bullet-proof. Never import directly from Excel. Open the Excel workbook and export the data to tab-delimited ASCII file(s). Even better, ask your providers to do the export to ASCII for you, and submit the ASCII file to you, so, you don't have to do it. Then, from SSIS, import from the tab-delimited ASCII file(s). From ASCII files, SSIS can import fields with thousands of chars, without a glitch. It really works. Try it!
Herndon Virginia - USA