I like SAM too. Except for rockets, VF units are wholly obsolete next to them. Regardless of whether the VF units below them were good or not, the SAM units are still better in 4 out of 5 cases so that's an improvement to me! And even rockets require a substantial attack bonus to be able to hold up against boosted SAM units, but there are very few situations where you're better off using them over sniperbots anyway (or something else entirely).