However, I really wish that, when using the back-panel dial to select the focus point, it would let you select auto focus point selection using this dial instead of having to switch back to using the exposure compensation button plus the main dial for this. I find it the best of the custom-function-selectable variations on focus point selection but it still feels really clumsy - the only weak point in an otherwise impeccable set of ergonomics.
Next, it's so fast! First, the speed of the autofocus is a great improvement over that of the 10, and second, the continuous-shoot speed: 6fps! Yes, that means you could get through a whole 36exp film in 6 seconds, but more importantly it means you can take a set of 3 exposure-bracketed shots in half a second.
Oh yes, and if you're into shooting IR film then this EOS is fine; it doesn't suffer from the problems many EOSs do with IR film counter diodes fogging the edge of the film as it uses a sprocket counter (for those who care: the EOS-10, EOS-1 and EOS-1V are also fine). It also has a solid backplate so the reflected IR won't look weird. (See photonotes.org for a fuller explanation of this.)
The battery life seems fine too: it does use 8 (!) AAs, but they last for about 65 36exp films and NiMH rechargeables will bring the cost down anyway.
In summary: the EOS-1N is a big step up from the EOS-10 in terms of both quality and performance. It is well-designed, feels extremely sturdy and has already produced excellent results. The interface is in most respects just right - everything you want is there, where you want it, and the cruft no-one ever uses has not been included just for the sake of it. It doesn't have the eye-controlled focus, number of autofoci or extreme weatherproofing of the latest EOS bodies (the 3 and the 1V), but neither does it have the price tag. Until 2000 it was Canon's flagship SLR and for less than 600GBP it is an extremely good value buy; I'm very pleased with it.
Note: I'm currently using it with the EF 50mm f1.4 USM lens and a x2 teleconverter, which are also awesome pieces of kit; I traded in my 35-135mm zoom with the EOS-10 body, and aim to replace it with a 28mm prime and some kind of good telephoto prime, either a 200mm or a 300mm. I'm also using a Jessops flash, which totally sucks and doesn't even take rechargeable batteries because the battery chamber is too tight a fit, but I don't do that much flash work anyway..