CPAP Machine Choices - read this before you accept a new machine

[DaveL]

Thanks Sleeprider and Revvysue. I've only had 2 Respironics bricks (yuck) and 2 ResMed machines. It's good to hear about high quality machines from other sources.
@Revvysue welcome to the forum. My treatment became tolerable and more successful when I came here and listened to the advice I received.

[Poolboy]

Hi again !   I just replied to your other post about purchasing a Lowenstein unit from Canada.  I did not mention I actually own a Prisma Smart Max then, because my comment was already way to lengthy.  
Her is some info on my Lowenstein and why I bought it.  I already have a ResMed 11 that's providing great results, and I love the machine.  While searching used ads for a cheep backup machine incase mine has a failure,  and to occasionally use at a secondary location, this Lowenstein with 1008 hours on it and a manufactured date less than two years ago came up.  It was priced really well,  so now it lives at my house.  
I initially set the Prisma up the same as my ResMed and expected the same results.  Not that easy!  Set on Auto with EPR and pressure range to match my ResMed it  produced a much choppier Flowrate graph with much more flow limitation showing at top of each inhale wave.  Not what I expected in lite of all the talk about their great Algorithm.  Then I did a few nights at fixed pressure and no EPR and the flow rate graph cleaned up a lot.  More experimentation is required.
  Also, on Auto the average pressure was much higher with many more ups and downs.  The machine records many more parameters of data as well, and clutters up the OSCAR charts with a distracting amount of event and condition flags.  The WCIKE Stormrider? suggested explains how to tame all that down and display only the most pertinent data. I still need to do that.  After just 8 nights testing the Prisma I needed to leave town for a few nights. To avoid needing to mess around with a new machine I took the ResMed and have been using it since.   I will get back on the Prisma in another week or so.  
- Noise - My expectation of a quiet night was met, sort of.  To start,  I will mention my hearing is excellent for a 60'ish year old.  With the Prisma located beside the bed at face level and about 2 1/2 feet away I DO NOT  hear it.  Whatever sound it makes is so constant that I don't detect it.  Compare this to my ResMed 11 and the Res 10 I trialed last summer.  They make a slight accelerating/de-accelerating cycling sound with each in/out breath, more noticeable above 9 cmH20 pressure.  BUT, with the Prisma I was suppressed to hear some noise near the top of my mask frame where the hose connects (ResMed F30i) with each inhale.  I hear much less sound from that location with the ResMed.  This issue may possibly disappear with a mask having hose connection in front of the mouth Vs top of head.  Just guessing.  
- The Lowenstein with humidifier takes up about 50% more space on the bedside table. 
 ResMed 11 WITH humidifier = 53 square inches / Prisma NO humidifier = 45.5 square inches / Prisma WITH humidifier = 72 square inches.  (The Prisma comes with the end cap at no extra cost,  which allows use without the humidifier.  The Res 11 end cap is an additional purchase and using it without a humidifier does not reduce its size very much.
For me,  the Prisma humidifier at its Max produces about the same humidity that the Res. 11 does near its mid point setting of five.  That is fine for me.  Navigation through the menus, and getting into the advanced settings is easy with just a bit of practice.  The humidity level can be changed very quickly without stopping the machine, and the ramp phase can be stopped and re-started on-the-fly too.  The display characters are massive compared to the ResMed's and do not dim down as ridiculously low like the ResMed does.  No more reading glasses needed for me when making adjustments, or shinning my phone flashlight on the light sensor to make it brighten its display screen. (ResMed must think customers with 20 year old's eyes are buying their machines !)  I almost missed the air filter.  it is a very large and thick foam filter designed to be washed and re used a few times before replacement.  Its porosity looks finer than my other units does.  but I admit air filtration is much more complex than meets the eye. 
- I get the impression of high quality and solid build from the Prisma, with no indication of skimping on weight or strength of materials as a way to get manufacturing costs lower, or to miniaturize it. I believe it is bigger and heavier in ways that make it a bit better (overlooking travel/portability in that statement).  For example the humidifier.  Thick strong plastic.  The manual says keep using it for-ever, providing good gleaning practices are used and you don't break it. The heating element screws into the tank and can be purchased as a separate part.  The ResMed 11's very thin humidifier tank is designed to be replaced every few months.  Mine has been treated with kid gloves and after 7 months has developed  a couple of small cracks in its lid section.  Can my Res. 11 be sent away for a new humidifier heat element if it crapes out?  I don't know,  but shipping, parts and labor costs would likely be involved.
- I'm  confident the choppy Flow limited inhales will be solved with some advice from the Resident Expert in this group once I get back on the machine and make the correct adjustments.  I have pointed out some aspects where I think the Lowenstein Prisma improves on the ResMed 11, but must re-state that I love my Res 11.     After I get the Lowenstein set up and providing results equal to the ResMed it will probably be difficult to decide which one I would keep if one had to go. 
**I forgot to mention the ResMed 11 has the humidifier Pre Heat feature which the Prisma lacks,  It provides massively more valuable info in its My Sleep View menu, Its on/off button is amazingly easy to find in the dark,  It has a much more modern menu interface and format,  a new humidifier cost about $60.00 here Vs about $325 for the Lowenstein Humidifier,  It looks more aesthetically pleasing to many. Obviously I am forgetting something.
I feel very fortunate to have my hands on two such amazing machines.
- Best of luck to you.