well your basic 03 RK starts at $16,215 and your 03 SERK starts at $27,995 then look at what you are getting for that extra money...
big bore cylinders $300
big bore pistons $120
new cams $260
stroker kit $1300
hydraulic clutch kit $700
profile reaer suspension $275
spun aluminum wheels $1220
mufflers and end caps $300
oil cooler $300
plus a long list of $50-100 items that more than make up the difference. and you dont have $6000 worth of take off parts in your garage. thats how i weighed the decision to get mine