To the best of my knowledge, the SR20 is not currently approved for flight in IMC. This information may well be out of date - it comes from a student of mine who was thinking of buying one quite a few months ago, and I know that Cirrus were working on getting it approved at the time. And anyway, now I think about it, I might be confusing the SR20 with the SR22. So don't quote me as saying that it's not approved for IMC.... but if this is (or ever was) the case, it could explain why you've heard that it's not approved for IR training.
As for glass cockpits in general, I've been fortunate enough to spend a few hours flying a glass cockpit Seneca V (and I hope to spend a few more hours flying it, too, if I can find people to cost-share with!) I have to admit I was surprised at how easy it was to adjust to - the dials and guages all work exactly the same way as a steam-driven cockpit, except that they're on a computer screen. There were just two problems for me: first of all, I kept reading bank on the attitude indicator the wrong way (i.e. confusing left and right bank), but I got over that after a while. And secondly, I found that I was constantly fighting to keep the altitude right.... until the person who was checking me out pointed out that I was only 20-50' off, which would barely be worthy of a comment with an old-fashioned altimeter. It's just that since the glass cockpit shows you the data more accurately, you naturally try to fly it more accurately, which of course is much harder.
So, on the basis of my experiences so far, I can't see any advantage of doing the IR in a glass cockpit at all. It takes next to no time to convert, and the extra cost is probably more than it would cost to convert to glass cockpit afterwards. The only thing I can't comment on is how employers would look at glass cockpit time, but I would guess that would be down to individual employers anyway.
Hope my ramblings are some help to you!
FFF
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