Did some research and decided on the Brisk Air II for a few of reasons.
First off: the Brisk is a bit less expensive compared to the Penguin by several hundred dollars.
Second: I've heard of some issues recently with more noise and vibration with strong harmonics coming from the newer Penguin II units v/s the Brisk Air II. Something to do with the additional stress that the new "Green" refrigerant puts on the unit. Changes include (plastic inner housing, different type compressor, different type refrigerant 410 vs 134a) The Brisk Air II was designed for this as the Penguin was more or less retrofitted for it.
Third: The weight difference. Although not drastic, it does reduce about 25lbs on the roof.
I went with the 15,000 BTU to help with the larger front cabin area. I don't believe that a 15,000 BTU Penguin unit was available in 1992 so the Penguin was only 13, 500 BTUs at the time.
I do wish the Brisk was lower profile, but I can live with that since my MH isn't what I'd call pristine. Just needed a good dependable unit for summer months.
The old Penguin kept freezing up or showing under power when run for long periods of time. Needed something that could run for days on end without problems. I've verified the power feed and it was always above 116V when the "Low Power" light came on. Also had issues with the auto fan speed control messing up and the heating element never would come on even though the element checked out OK.
The last issue was with parts. As I was looking at doing some repairs on my Penguin I found that some key components like the main board were no longer available and those that still carried them were pricing them quite high. The inside plastics were looking a little dingy as well.
Figured the new Brisk II would have a long time of parts availability and a two year warranty to boot.
Any other gotchyas in the installation process? Anything I should be getting in advance? If everything looks like it should I figure it'll take about an hour to an hour and a half to remove and install. Already have the inside control disconnected.
My plan is to remove the top unit intact so I can use it as a spare for the back unit. Maybe sell it to someone needing a replacement on Craig's List.