Another thing, don't get stir bars with the rib in the middle....they will rattle and drive you crazy if you are anywhere near them.
Cheers,
Bud
I bought one of these and true the noise is a pain, but as my stir plate like all my brewing stuff is banished to the garage I don't find it an issue. On the positive site the ribbed stir bar works well in a flask that has a slightly concave base as a lot of the cheaper ones do.
For the stir plate itself I followed these instructions, cost me almost nothing to make, just used the cheap magnets from Jaycar and it works great.
Cheers Stu