I got back into riding about a year or so ago. i started back up on a Electra townie and after a few months I wanted something different. I can't seem to pass by a trail without checking it out and the townie wasn't up for it, so I sold that. Currently I'm riding a Giant Roam 2 and it's ok, I like it just fine on pavement but off road it's not great (it has stock hybrid tires on it). Living in florida I ride very rutted trails and have to cross alot of deep sand pits and I'm struggling on the roam. So I decided to get a second bike , should I put some hardcore knobbies on the roam , and keep it as my off road bike , or should I buy a new mountain bike and keep the roam for the street? I have about $600 to spend so what bikes should I be looking at? I'm 5'8 225 lbs. I don't want to change out the tires every time I switch my ride so I do want another bike.