  It is shown, that the Gamow-like model with only one adjustable parameter -
radius constant is able to reproduce well the alpha-decay half-lives for all
even-even nuclei with the proton number larger than 50. The systematics for
odd-A and odd-odd isotopes can be also well described when ones introduces an
additional hindrance factor. Similar model based on the W. J. Swiatecki idea
from 1955 is developed to reproduce the spontaneous fission half-lives of
transactinide nuclei. The achieved accuracy of reproduction of the data is
better than that obtained in more advanced theories.
