Long time RemStar 510M user, looking for replacement

[michaelthomas]

I've been using the RemStar 510M for over 19,000 hours and it has been acting up for a few months now. When starting up it will sound like the blower is starting then it will fizzle out and you can see the device reboot. Eventually it gets started. It does this once and while but has been happening much more frequently. I haven't been using the humidifier but I am thinking about starting to use it again.

I was going to take it apart and see if I can figure out what is wrong, but I don't have a long enough T15 to open it. I had some questions I was hoping you guys could help with.

Can I just order a replacement from CPAP.com if i just want to buy something myself or do I need doctors approval before doing it?
I was going to call up my DME and see what the process of replacement is, and if I will be able to chose a better quality unit like the RemStar 60 or AirSense 10. ( I hear the Air Sense 10 is excellent, but what is the big difference between them?)
I've been using the full mask quattro mirage pro medium, I hate it, but it is all that has worked for me. As the bands get older I have to tighten it more and more. I generally have it extremely tight which has caused pimples and sores on the back of my neck as anything loser causes leaks and drives me bonkers. I want to try other masks, but at $300 a piece I haven't wanted to buy a bunch to try. When I first got the device, they let me try a bunch of them but not sure how it would work if I need to change to something more comfortable.
Will I need to do a new sleep study to get them to replace the unit? I really don't want to go through that again.

[JDS74]

The 510M is the RemStar Auto-A-Flex model and you have had yours for quite some time (maybe 8 years??).
If you have a copy of your original doctor's scrip, then you can just order a replacement from CPAP.COM.
If not, you can do one of two things:

1) buy a slightly used model from another member of this forum or from Craig's List.
___The model 560 would be equivalent in the 60 series, DreamStation Auto CPAP in the new series.
___You should be able to get a very lightly used 560 for less than $400 plus shipping.

2) ask your doctor for a new scrip and get a new DreamStation from CPAP.COM with humidifier for about $900.

BTW, if there is a Harbor Freight near you, they have long T15 screwdrivers as do some auto parts stores.