Don't worry about the price of turbo plugs to much as you'll find they are dearer to buy initially but they last longer than a stardard plug does (in my experience anyway) so price wise they work out about the same in the long run.

I use Novarossi C5Tc or C6Tc turbo plugs (Long body plug- I know everyone tells me you can't use the long boby turbo plugs in a go but I have been for nearly 2 years with 0 problems so far)

Os P3's seem to be the main choice for Go users but fuel, pipe and track conditions (ambient temp) will all effect the plug temp and type to use.

hope this helps

Adrian