1080 is superior IMHO. Darker tube = better contrast. Blacker blacks, whiter whites kind of thing. Tube had a matte finish also, 1084 is glossy and comes with all the glare a glossy screen is known for. 1080 was built better too, as far as I can tell. I've seen way more blown up 1084's comparatively. Iffin' I'm not mistaken:
1080 - mono and made by Goldstar (later made tubes for Zenith)
1084 & 1084s - the 's' is for Stereo and made by Philips of Philips/Magnavox fame
1084SD1 - stereo, last of the reg. Commodore RGB line and made by Samsung
Oh - but the one thing that SUCKS about the 1080: it's either PAL or NTSC. Cannot switch to either, unlike the 1084+'s :-( Many, many, many Philips tubes were shipped misaligned. Their RGB guns as it were. Not a seriously huge problem if you know how to calibrate, but still. I'd also say that the image might have appeared sharper on the 1084, almost as if the dot-pitch spec was higher, but not until you properly aligned her. I'll always have a penchant for the original 1080 though :-)