Cadillac: Suitable struts for a '90 DeVille?

I've seen catalog solutions ranging from $244 for a complete "SensaTrac"
assembly, to $30 or so for Gabriel Guardian struts, and many in-between
choices. I do not wish to do this job more than once in the remaining
lifetime of the car.

What would be the most cost-effective solution for a moderately driven
Caddy?

Thanks!