I activated an XL4 on 5/12 with Cox in Orange County, CA. I am using a Motorola M-Card/TA combo. It took a few hours and a couple of reboots for the activation to stick. Once it did, I have had 0 problems. Tivo Suggestions is on, and it has recorded hundreds of programs during that time, often using all tuners concurrently. I received the 220.127.116.11 update right after, and it survived the reboot just fine. This is definitely one of those YMMV situations. If I had the problems that some others had mentioned, though, I would be wary as well. Right now (knock-knock), I am very happy with the XL4 and the Premiere I am using.