Its been just over a week now since I got my 510. WOW!!!!! I feel amazing. I can already tell a huge difference in the way I breath and the way I feel. This things are awesome. Ive had a couple of analogs. Not so much that I needed them. Just to compare. I dont miss them at all.PVs are where its at! Thanks for all the info from this forum to help me get started.Bless!