all-in-one rigs compared to seperate rigs

The overall market for 222 MHz gear is very small, and is "zero" in Japan, where most of the stuff is designed.

Neither Europe nor Asia, two huge users of the weak-signal spectrum on VHF-UHF, have any 222 MHz allocations. We're the only ITU Region that has any, and we've proven to the manufacturers time and again that, by and large, we're not much interested in the band: When 222 MHz modules were being manufactured and readily available for some multiband rigs (like my Yaesu FT-736R, for example, which covers any four VHF-UHF bands you like and was on the market for more than ten years), almost nobody bought them.

I like separate rigs for HF and VHF-UHF so I can listen to different bands simultaneously. It's common that I'm on 20 meters, and a local friend gives me a call on 2m FM, or the band starts to pop open on 6m, and if I didn't have separate rigs listening to those places I wouldn't know it.

WB2WIK/6

 

As whether separates or all banders are better:  When you put more in a box first thing that happens is the price tag goes up. Next thing that usually happens, since there is more in the box to break,  something is more likely to break. When you try to cover DC to daylight, as some do:  100KHz to 2.4 GHz you have many more band switching circuits and other special considerations for the frequency extremes. Also the more you cram in a box, without significantly increasing the space you create a heat problem. When you have a 24000:1 frequency spread there has to be some comprimises somewhere. Simpler units with 10:1 or 20:1 frequencies spans even have problems, but not to the extent as the extreem spreads of the super high tickets radios.
Consider the difference between a Cadilac and a Chevrolet,  or a Cadilac and a Jaguar. The Cadilac on average spends more time in the shop than a Chevy, and a Jag spends more time in the shop thad a Cad.
My analysis of the situation.

 

At the moment I have separate rigs for HF and VHF/UHF and also an FT-100D that covers 160-UHF. That for me is more than adequate along with a general coverage receiver to listen to other bands.

As to what I'd like, well, I'd like a rig for each band, of course! I'd also like the room in the shack and the antennas for each one, otherwise they are useless. Let's see, that would be 160, 80, 75, 40, 30, 20, 17, 15, 12, 10, 6, 2m, 220, 440, etc., etc. Don't forget the proposed VLF band and also the proposed 60m band. Yep, I'd definitely like to have a complete rig and antenna for each one!