Thanks jlinkels and ownos
and sorry it has taken so long to reply
@ jlinkels: From research rather than experience, Tryton has a much cleaner code base than OpenERP, addressing the issues of "sloppy development, zillions of bug half-fixes, patches and regression errors
". IDK about the upgrade data migration issues. Tryton does not have as many modules as OpenERP.
@ ownos: thanks for the information. How does Tryton perform for you? We are concerned about response times even in our initial explorations with very little local code and almost no data.