Plastic spinners are very common and generally work just fine. I've seen a few that come with cheapo ARF's that were problematic but most quality plastic spinners are no problem.

Your super Tiger will be very tight when cold, especially when it is new. Try turning the engine clockwise (looking from the front) until it comes up on compression. Then get your starter spinning while not touching the spinner. Now quickly push the spinning starter up against the spinner. Usually this will work.

Also a few drops of oil on top of the piston and manual cranking by hand for a few minutes helps too.