I mostly start in second gear. In the 2 stroke days it was always 2nd sometimes 3rd, never 1st. Just curious to hear what gear you guys use most for starts.

i like second two when the darn thing wont stall LOL

You'll fly on the 450R when you take off compared to a 400.  The 06-08 450R's have higher compression than the 04-05 do when they are stock, so you already have a power advantage over the 04-05 bikes.  You should get off the line really quick with an 08, but you'll need to start upgrading to hang at the track.

How did you break it in?  
 
Proper break in is of utmost importance.  You should run the bike HARD in 2nd, 3rd, and 4th gears and then use compression braking (letting the motor slow the bike down) to acheive proper ring seals.  Ride 15 minutes pinning it in 2-4 gears and compression braking and then park it and let it cool.  Make sure you let the bike warm-up properly as well before riding EVERY TIME for the first 20 hours.  Change your oil after the 1st ride (as well as filter).  And use regular oil, NOT synthetic for original break in.  The second ride, warm it up, then run it hard for about 30 minutes.  Continue running it hard for the first 20 hours, and make sure you give it plenty of rest time after riding.  Change the oil again after 20 hours, and then switch to a synthetic oil.  Proper ring seating is the most important thing to do with a new bike.  OEM recommends riding it easy, but that doesn't give you a good seat.  Running it hard makes the rings basically etch their own grooves and matches the rings to the cylinder wall much better for a tighter seal.  If you have ANY questions about breaking it in, feel free to ask.

You need to change the oil more frequently because you will have very fine metal shavings from the rings cutting into the cylinder walls (it's supposed to do that).  Change the filter as well.  Once you hit 20 hours, you should be good.  And just a point of reference, the valves need to be adjusted after 20 hours as well, so take it back to the dealer, or do it yourself.  Then you can wait till it runs for 80-100 hours before the next valve adjustment.