I am starting to weigh my options for a new exhaust for my 2007 WR450F. Currently I have a 2008 YZ450 header and muffler on there now and I am pretty happy with it. Way better than stock WR Exhaust, but I do need a spark arrestor for it. Trying to decide on which option below is the best route. 1. Get a PMB spark arrestor for the stock YZ exhaust. Pretty cheap overall at $130 plus rivet gun ect..... 2. Shop that sponsors me can get me a Yoshi slip on for the YZ header for $230. So $100 more than the PMB and im pretty sure I can sell the 2008 muffler for that or close too so probably a wash. 3. Shop that sponsors me can get me a Dr.D complete system for $380. So $250 more than the PMB but i figure I can sell my complete YZ exhaust for $150 or close so out of pocket $100 for full system So my question really is which is worth it? I know Dr.D exhausts work awesome on the YZF bikes but is it much better on a WR over a YZ exhaust?