My mother is in that catchment area and, from reports from friends and professionals, Belvilla would have been my preferred placement for her when it became impossible for us to care for her at home. As it happened, when the time came she had become too dependent, there was no long term place for her there and she moved to the Meath Community Unit instead. I gather that Belvilla has more mobile/alert residents than the Meath. All in all, I would think you should have no qualms about Belvilla. If you think your mother will be ok with respite (wherever) then I'd say go with it.
mf