I had a grace frame, and now have a Handi-quilter. My Grace frame came from KathyQuilts with leaders they made (not from Grace). I don't recall if the Grace were attached with velcro, but I think they were. Handi-Quilter are attached with velcro.
You may want to consider if you want to use something like Red Snappers, as they may need a specific type of leaders. I just pin and can honestly say I don't think there was as different in the use between the two. I've not had any issues with the Handi-Quilter, and don't recall any with the ones on the Grace frame.