Though EVERY RPer could use the spell check so not THAT accurate all of a sudden any more, is it?
Really, I think you interpreted too much into that.
And I am actively using Firestorm by the way and couldn't be any happier. I absolutely dreaded the official SL 2 Viewer for many a reason but learned to cope with it - when I switched to Firestorm it seemed much of what I loved about Phoenix + multiple tattoo layers = happy me.
I agree though, the spell check is something I totally miss out of obviously practical reasons and I'd not mind the character limit to be gone. Can help yourself out with >> or * for the next post but yes, it'd be better to just write and post it all at once, no doubt.
What the Pancake posted about the inventory-search actually bugs me more than those two things together, makes searching for something in your inventory while you go through your recent purchases a pain in the ass, putting an outfit or avatar together.
Another thing I noticed, though I am not sure if it's either a viewer issue, or a settings issue or god knows what: when I am ALT+Left Clicking something and spin around it - say looking at an avatar or my avatar to see if everything looks alright, it sometimes randomly moves my character while I am still holding down. Never had that issue but those last days I noticed it somehow...annoying.
Login is a nuisance but something I am not too annoyed by.
Otherwise, it's as close to my old phoenix/emerald optimum as it gets. Wouldn't switch back.