I found a used 04 RM Hammer for a good deal online. I am 5'10/11 and 170-175 with an inseam of 32. The bike is a size 17.5. The thing I am worried about is the size. I looked online at Rocky Mountain bikes and they have the stand over height of 743mm which is like 29.25 in, so it should give me a good 2-3 inches clearance which is perfect. I am sorta between the 17.5 and 18.5. So the 18.5 is just like 3/4in higher than the 17.5. It also has a top tube length of 565mm. I heard someone tell me that RM tend to be sized shorter than other companies. So a 17.5 in a RM would be more like a 16 in another company. Is there any truth to that? Or can I get away with the 17.5?