Go here and see what is recommended:
http://www.antennaweb.org
He should be fairly close to all of the towers, so it may not be a problem. Does he get all of the analog channels clearly now? If so, then he'll probably be fine. The thing to remember is that the digital stations are still broadcast on standard UHF channels. So, if one works well, the other probably will also.
Now,whether to get the TS-160 or not is a better question. My advice is to wait until the firmware upgrade comes down in the next few weeks. We'll see how many problems they solve (or create). If you don't care about DVI, the Hughes E86 is a good choice and is $100 cheaper. Otherwise, the Zenith/Sony units, but they're $100-$200 more expensive. The TS-160 can't be beat for features, but it does have some problems. Some say the other units have they're own unique set of problems, so who knows.
One thing is for sure, there is no problem free HD receiver right now. They all have some problems. The technology is still fairly new. They all work, but you just need to face the fact that none of them will be perfect.
Dave G.