From my experience, when there is no 4G signal it will continue to display "Scanning...". I recently got my 4G back up and running with the new kernel. I have been testing my 4G signal to make sure there aren't any more problems. I do ALOT of driving around the Philadelphia area (in and out of 4G coverage areas), and given the recent problems regarding the OTA update and 4G, I am CONSTANTLY checking my 4G to see if it is working. I can honestly say, it has held a 4G connection so good, I dont need to have 3G on anymore when I am in Philadelphia.
When I get back home I will download this rom and try it out on my evo. Chris' roms were ROCK SOLID on my TP2, and I know this rom will deliver. If there any problems I will report back. I had Sprint send me out a replacement Evo. I have been experimenting with my old one to find out what exactly I need to do in order to have everything functioning 100%. I have about 3 more weeks left before I need to send the old Evo back in to Sprint.
If there is anything that needs testing, please let me know. It gives me a reason to play with my phone.