You all make good points. I have some definite views after extensive digiscoping different ways; getting SOME good results with all of them: first hand-held/no sunshade for 3 yrs.; then Xtend-a-View mini and my own design camera mount for a year; and now still with my SDA-100 mount design and the Xtend-a-View Pro Variable.
First point, emphatic: use a sunshade magnifier! Last week I took life-bird photos of Red-naped sapsucker... there are three posted to my gallery. I had the variable Pro shade on order but did not have it, and my old Mini-shade is for 1.5" LCD whereas my new Olympus C-60 zoom has a 1.8" LCD and you can't read your important settings in the LCD if the hood's too small for it.
Here's what happened: The sapsucker shots are all under-exposed. I barely salvaged them with extensive Photoshop levels/ dodge and burn. Why... no sunshade. The C-60's LCD is supposed to be a new better-in-the-sun display, but I couldn't see exposure values well enough, so what'd I do- I turned up display brightness. I used 3x reading glasses going on and off me just to see without the shade-magnifier, and stumbled over branches etc... now the subject was bright, but it was illusion, even in the playback, I thought I had good exposure, but it was underexposed! If you play your camera shots on the TV for quick editing you see this effect, it'll look like a good exposure then you get it on your carefully adjusted PC monitor and it's underexposed!
Two: without magnification, how can you see composition, bird-body position, focus and exposure values? I certainly can't. The Xtend-a-view Pro Variable has up to two diopter focus adjustment! Finally, it's not out of focus like the regular Mini one was after its velcro held it away from the LCD a little too far. Also, they claim that with the Variable Pro you can "detune" slightly if the "hard" pixels bother you. I find it to have excellent range of focal adjustability... that is a lot of rotational twisting makes for small changes in focus... you should be able to find just the right focus for you.
Three: I never believed you could bird and digiscope by fixing the camera to the eyepiece. I always felt this was too big a sacrifice, and I'd end up enjoying neither: first missing a shot by keeping the camera un-mounted; second, by having to view some of the bird activity through an LCD even if I wasn't shooting at the exact moment, and then again missing some viewing through the scope while I fiddled with screws, etc. THAT's why I bought unthreaded lens cameras and HAND HELD them through three years. Finally it dawned on me we just needed a different type adapter that swings away, and I designed what became the SDA-100, but it's for straight viewing scopes only; if I get around to it we'll work something out for angled scopes too. I want to add: other BF members made swing-a-way mounts before me if I remember correctly, and graciously shared them with all, the spirit of BF! but they didn't fit MY setup, they fit only theirs. What I did differently was just build in a great amount of adjustability in my design.
After attending a Swaro-sponsored digiscoping workshop with Clay Taylor the Swaro photo pro, I see some good reasons for angled body scopes besides looking higher up easier. I believe my next scope may be angled, but only when there's a digiscope mount for it; mine or a different brand that swings away quickly and easily.
Fourth and final note: you can hand hold alright, but I feel a sunshade is a must. However with a mount and remote shutter I routinely get good results at 1/30 sec. shutter... all you have to do is take enough frames to catch the bird once/ not moving. Even hummingbirds with their side to side continuous head swing pause enough to get many good frames. I slow shutter shots to be absolutely impossible when hand-holding the camera... as most web advice will concur; and you're no better off with a mount if you don't have cable or remote release, or are in a big wind, or anywhere near stampeding elephants!