Documents over 50MB are just not cool. They will also prevent a conversion to Best Practice.
Here is an SQL query to find any documents over 50MB.
I am using an incorrect multiplier of 1000 because this will catch that and the correct multiplier of 1024 as well.
select MAFile.fname, MD.itemid,MD.PatientId,MD.PatientName,md.DocTitle,md.DocDate
where MAFile.fsize > 50000000 and MD.itemid=MAFile.itemid