Everybody will have an opinion on this. Generally, a trailer of some sort is a good choice if you plan to stay in one place for a while--like a couple of week or a month. If you already own a pickup truct with a tow package, it is also the cheapest method. Fifth wheels are easier to pull and have more storage. I have a motorhome because it is easier for one person who keeps on the move. I can be unhooked and on the road in 4 minutes, not counting driving to the dump station and dumping tanks. (It takes me much less time to unhook and head to dump station to dump tanks and then return to campsite than my son, who has to go through a longer hookup and unhook when he gets back. I can be dumped and back before he hooks up!)
I also chose a motorhome because it has more storage for a full-timer like me, and I can stop at a rest area to take a nap, or fix a meal, without going outside--better security. I also don't tow a car, which means I have to drive my motorhome to a grocery store, but that is minor, at least to me. Other people say they could not live without towing a vehicle, but that makes it harder to go through gas stations, etc. while you are driving.
Basically, it all depends on how you plan to use your RV and what style of traveling you do. I have driven 154,000 miles in 9 years on the road.