a wheel is simply a way to cover a pool of numbers, so they are all in play.
optionally it can be done in such a way that it offers a base match guarantee.
the degree of coverage for either is up to you & your budget.
however, trying to play the entire number field AND have a base match guarantee is not practical.
as you mentioned, you could play 2 wheels just for the sake of having every number in play.
let's see, it'd cost $44 to play 2 wheels which offer a match 2 base.
22 numbers in 27 picks:
http://www.ccrwest.org/cover/t_pages/t2/k5/C_22_5_2.html.gz
remaining 17 numbers in 17 picks:
http://www.ccrwest.org/cover/t_pages/t2/k5/C_17_5_2.html.gz
you should back test such a scenario and see how it'd perform.
blitzed
