Both have Pros and Cons, Cost wise maintenance wise the 2 stroke is easier in my opinion, The cost to Hot Rod a 4 stroke is how much money you got is how fast you can go, pipes $500, Pistons $250-$400 Larger Valves 55 to 65 Ea Porting the head $350-$1500, Carbs $250-$500 EFI Programable Controllers $250- $500 CDI Box $250 -$500 Cams $265- $400 H/D Valve Springs $125- 250 it all adds up, not counting Big Bore Kits , Stroker Kits, easy to spend $3000-$5000 for 60-65HP 

Where a LT500 for around $3000 for complete rebuild Bottom End Top End - Porting - pipe - carb 65 to 75 HP 

But hey, I love my DS730..electric start ya know.................