I'm working with a couple of lists now, one has 10k rows, another 14k. Once you're in and the cache refreshes, it's smooth sailing unless you are doing an update query impacting many rows. Bound form operations work just fine. Granted, I don't have more than a couple dozen users. It's important to remember that updating many rows means that not only must you run a long query against SharePoint, but that those same updates must be downloaded into each user's cache. I've learned to not only version my front-end, but also my back-end. I use a version table to determine if there have been design changes to the lists and call CurrentDb.TableDefs("tbl_name").RefreshLink only as needed. And, I only force people to get a new front-end if the current code/query/form/report changes are critical. I expect that these practices will reduce delays for users and reduce inadvertent loss of their updates as design changes occur.