By Jane Engle Rent an RV, hit the road and save gobs of money on your next vacation.Really? Maybe not, even some advocates concede."You could probably pack four people in a car, eat at restaurants, stay in hotels, and I imagine it's about the same cost," said Chuck Woodbury, editor of RVtravel.com, a consumer website offering tips and tricks for RVers.But consider the intangibles."The real advantage of the RV is that the family's together, and you can cook and eat healthy meals," Woodbury said.