Well after modding the hell out of my A1200, I'm thinking it might be time to sell up and purchase an NG.
Getting all the hardware/software mods to work together was and still is enjoyable, yet frustrating task.
With the slow updates on mediator drivers for both the Voodoo 5 and Radeon 9200 it's really holding AmigaOS 3.9 back. Rattes updated Radeon driver was looking like the answer but Elbox trampled that.
Also getting any information/response from Elbox is impossible. Which adds to my frustration when spending quite a bit on their products.
Reliability is another factor, with all those different hacks/patches running it feels unstable now and then. The most annoying part is getting RTG/AGA switching working with WHDLoad, which wouldn't really be a problem with an NG. I've given up on this and run in AGA most of the time, although I don't get the pretty 1920x1080 with AFA OS/Zune desktop.
I have Quake/Quake 2 running great using Warp3D/MiniGL at 640x480. However Quake2 can be flaky and I get the odd software fault and it wont load. Another frustration.
Duke Nukem is fairly smooth except for a slight pause when some sounds load, but this would be resolved with using a FastATA, however it doesn't fit with the Indivision AGA MK2 and Mediator. :-/
Browsing is very useable, Ibrowse is fantastic. Although due to it's out dated browser engine a few websites don't display correctly. NetSurf is fantastic though, can feel slower than Ibrowse though but I think this is because it loads the entire page in one hit instead of loading parts of the page.
Flash, even with the Ibrowse plugin is a no go. Java stuff seems to timeout most of the time so I turned this off.
iGame/WHDLoad works really well (once you are running an AGA workbench) and the speed at what games load at is amazing. Forget floppy disks! :-)
99% of the demo's work great, no issues.
PPC stuff, I maybe tempted to purchase a PPC card for the A1200 but price wise I'd be better off buying an NG. The amount of money would buy me a nice setup, unless I can find someone throwing a card out (yeah right).
As a day to day machine, almost possible. The A1200 does an okay job :-)
Anyway I think I've accomplished (95% anyway) what I set out to do, I'll probably regret selling it. You always get that doubt with Amiga hardware, especially putting so much time into it. You become attached.
I'll go back to pondering it :-)
From my experience MOS on a Powerbook is a decent system. It can't do many HD formats well, but most 720p plays just fine. Browsing is very decent with OWB 1.23. All the applications I used on Classic hardware works fine. The user experience for the OS via Ambient is a great desktop. To me it feels like what Amiga OS 3.x should have evolved into. The authors of the OS are a great bunch who constantly update and enhance the product.
Looking at the total cost of ownership, MOS is the best value and experience for an NG Amiga...
I sold my 1200 and I don't miss it, I never enjoyed hacking at it to get it to work. Big box Amigas are more reliable and expandible. I still prefer certain things on my classic amiga, mostly for nostalgia. I always have had a soft spot for the 3000 and still find reasons to use it even if it could be done in MOS...
For games MOS is fast and fun, Quake 1-3, Duke, and RTCW all work great and at very playable speeds.