What are the possible problems with riding a bike too large?
At 48-52cm seems like I am riding larger than others my height on this post.

I bought a fuji at LBS they measured me to fit a 43cm, I am 5'4. After only 20 miles or so, I took it back. I was totally uncomfortable, regardless of where I put the seat. In frustration went back to old fathful 17.5" trek950 MTB w' slicks, no prob. Love it but sometimes, top out pedaling speeds.

I now purchased a used 48" cm trek road bike (WSD), a used cannondale R300 50cm, and a 52cm novara flat bar road bike, store return. Plan to ride them all to achieve a fit then sell those that don't fit. Already finding I don't have the heart to sell any of them though. On the trainer the 50cm feels best???

Important note: I do not have big money for a bike, my HB is pissed over the 3, I bought for less than $800 total, the cost of the original fuji, i returned.

Anything I absolutley have to know?