Someone posted a tip about securely attaching the needle tips. She said that if you hold the little key with one hand and then use one of those grippy things for unscrewing bottle caps to tighten the needle tip it works great. The one I have is round and looks like the waffled stuff you use to keep scatter rugs from slipping. I keep it in my needle bag for attaching and loosening the tips.
Good luck with your Options! I love mine!