QUOTE(lalapianolala @ Apr 29 2010, 01:27 PM)

well yes i am grade 8 but what i meant is personally for you, like what techniques do you find difficult in the etudes. oh, and thanks for the link:)
Personally? As I said everyone is different. Some top class pianists (e.g. Gulda) played them in private but refused to play them in public because they were not satisfied with what they could achieve.
Anyway, here is what I have found in the few that I have made a serious effort to learn.
The Revolutionary (Op. 10 No. 12) is the only one I studied in my previous piano-life - i.e. 20-odd years ago. I had to learn a few new techniques in the LH, but it is definitely one of the less challenging of the 24.
No. 3 would be easy(ish) if not for that Bravura section in the middle. You might be one of the lucky few that does not find it troublesome. Most people make the mistake of learning all the rest then finding that the Bravura - though musically simple - is harder to play than they ever imagined - and giving up on it. You should really do it the other way round. Slowly and patiently master the Bravura section (it might take months) then learn the rest to wrap around it!
Op. 10 Nos 1, 2 and 7 are supposed to be three of the most difficult, but I did not find them difficult at all. I never doubted that if I did the work systematically and regularly I would eventually master them. I am sure that I could have learned them when I had recently passed Grade 8, if not sooner, if I'd had any interest in them back then. Also Op. 10 No. 4 is supposed to be horribly difficult, but I am learning it now and there is really little to fear in it. You just have to decide on a workable fingering, learn the notes and repeat them carefully 'til it becomes fluent.
On the other hand Op. 25 No. 2 is supposed to be one of the easier ones (at least according to Eleanor Baillie) but I find it anything but easy and cannot make it sound convincing. Op. 10 No 8 is another that seems to have been composed especially to frustrate me. I despair of ever being able to play those semiquavers with the smooth-flowing elegance they deserve. Another tough one (for me) is Op. 25 No 4, with its big LH skips up and down the keyboard, at speed.
Op. 10 No 9 and No. 11 (nasty huge broken arpeggiated chords) are two more that I am still struggling to get to grips with.