well most of the time i tend to play hybrid since AS on cho hugely boosts his damage between his pretty godly base damage and his WHOMG vorpal spikes damage which is boosted further by AP.
my builds contain rylai's 80% of the time. as vorpal slow is basically the same as having frozen mallet but also boosts rupture, silence, vorpal, and feast damage.
but basically if i ever play tank, chances are I get ranudin's+ nashor (which is the full 40%), or ranudins + soulshroud which tends to be plenty or ranudin's + frozen heart. as taric all are equally likely. heck.. as taric most of the time i find it hard to choose between items because i already have the full 40% but want to use another item which still has CDR on it.. typically against DPS (AD/AS) heavy teams ranudin + frozen heart + soulshroud is kinda common for me even though its wayyy more than the cap. which is why im asking.
usually im out of mana (and or dead) rather than dying before my mana pool is empty since most of the cds on Cho and taric are fairly low. mana tends to be a problem but as taric i take clarity (sometimes at least) and i tend to take tear.
my full page is Apen/dodge/CDR (half flat half /level) 2x health quints + 1 move speed quint. between boots + not getting nashors, i tend to end up with zeal, either lichbane or leviathan in some cases both and it helps both chars be able to chase for stun/popup/feast. as my playstyle is fast tank/support, get in, cast, tank a few hits, get out so i dont get focused entirely.
anyhow, yeah. thanks for bringing that up. i totally missed the mpr/5/level runes. those are much more in line with what im looking for. I just feel way too squishy early game against the likes of ryze and viegar and nidalee that i would consider MR runes or.. Mpen to kill them before they kill me. but i dont see that happening much as they have much better burst and are basically AP only. I guess i will be trying the mpr/5/level runes for now since they are cheap, then work on Mpen/MR as i get more IP