i dont like the ifonz , but i love sms-chat and it works well on almost all the Custom Roms out for the TP. ide say also look into getting a "Clean Version" of a Rom you want and add the ifonz to it as it will probly perform a little better cuz, clean roms are a bit faster, no HTC Bloatware or carrier Bloartware. also check out the Copper Rom.
as for it getting cooked in, i doubt it, there isnt as high a demond for it since TF3d, TF3D2 and Titanium. Not to mention all the other 3rd party UI's out. Just a thought.
Good luck bro.
Edit: have you tried Winterface? its not free but it has a free trial. its fast and really intuitive. meshes well with SMS-Chat since its made from the same Developers.
http://vitotechnology.com/vito-mobile-shell.html