The choice of leading edge aspect ratio (AR) plays a crucial role when planning boundary layer experimental wind tunnel tests on a flat plate. Poor selection of the leading-edge profile hampers the effectiveness of the experiment and increases testing costs associated with interchanging of leading edges to attain accurate results. Thus, the appropriate selection of the leading edge is a very crucial part of the wind tunnel experimental process. The authors, in this paper, argue that the curvature of the leading edge and thus the AR are of paramount importance to attain accurate results from wind tunnel testing. In this paper, the authors have tested 7 different elliptical leading edges and compared their performance with an ideal leading edge with zero thickness. Experimental and computational has been presented for leading edges ranging from AR6 to AR20. Results were evaluated for boundary layer transition onset location and it was found that AR20 has the least influence on the flow structure when compared the ideal leading edge. A study of the flow structure at the stagnation point indicates an increase in adverse pressure gradient with an increase in the AR but also a decrease in the size of the stagnation region. The presence of a higher AR leading edge reduces the turbulent spot production rate which is one of the primary causes of boundary layer transition. The authors have presented a correlation which makes it easier for aerodynamicists to quantify the impact of the leading-edge AR on transition. A case is also presented to compare the relative performance of a wedge and the higher AR leading edge which gives potential researchers the choice between an elliptical or a wedge-shaped leading edge.