Welcome to the builders community. I think the advantage that the 750 has over the 701 is the seating. The 701 is what it is and can get uncomfortable on long flights.
I have modified the 701 pretty significantly as you can see, including longer wings, horizontal stabilizer and elevator. With the stolspeed VG's applied it flies great with little to no nose drop on stall. I did incorporate the 750 wing design in the longer wings but used 701 rib spacing to keep the strut attachment points in the same place and use the 701 fuel tanks. I also reinforced the fuselage a bit for the modifications. Quite a bit of research went into this before finalizing the design and I am really happy with the results. Definitely not a stock 701 anymore, more like a 725 :)
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