I agree, I never put in final pots - mostly because I want to know if they are going sprout and cant afford to waste the soil. What I do is use decomposable card seedling pots (from B&Q I think) which are about 250ml each and put then in a plastic container filled with soil (probably equivalent to jifi seedling pelets) . I do this because the really small pots I use are a nightmare to keep watered - they dry out in hours, so the the soil in the container helps hold water (this could be why the cling film or high humidity method started). This also has the effect of me be able to lift the pots and check if any roots are growing out the bottom/sides, and if so, they are ready for transplant and I pot into their final pot without breaking the root ball but knowing they are going to expand into it. By this time the plant is usually at least 3-5 inches tall with two sets of leaves.