Hi mate, you could have guessed I'd be looking in on this couldn't you
1. Well I'm no pro user of camcorders so I'll leave the recommendations of the best cam for you to the pros such as Roy Mallard. He'll be along in a while I'm sure.
2. The actual file that is written to a DV tape is the same wheather recorded on a £200 or £2000 DV camcorder and therefore will be handled exactly the same by the editing program. The better camcorder will just get a cleaner picture onto the tape.
3. The Z1 is probably your most future proof option - at the moment. As soon as the price starts to drop a new & better model will be just around the courner. So at what point do you bite the bullet and buy?
The Z1 can record SD onto a DV tape, so can be used now as a great quality SD camcorder. Or you could record as HD now and just capture as SD to the PC until HD-DVD/Blue Ray become available as an output medium. You can then go back and reedit as HD your old footage and get the best of both worlds.
At something like £4k for the Z1 it is a massive investment, so I would strongly suggest getting as much advice as possible, and definately a demo of it. After all, all the above is only my opinion and therefore really should be ignored at all costs
Mark.