Laurie,
There are wide variations in absorption of CoQ10 depending on the type of pill: powder,softgel, Q-gel...
So taking one that has high absorption, reduces the number of pills necessary to achieve a certain blood level of CoQ10. This may lead to lower cost & be more convenient to administer.
You can start your search at
http://www.consumerlab.com/results/CoQ10.asp
A recent addition to the list of suppliers is Life Extension which claims that their new product (with limonene) has the highest bioavailability (difficult to verify against all other makes except the powder type which is ranking lowest in absorption):
http://search.lef.org/search/default...ts&query=coq10
Nearly all (if not all) CoQ10 is made in Japan. So if you have a friend over there he might be able to get it for you at a lower cost.