I think the overall criticism of this show is too harsh. It didn't have the budget of _Lois & Clark_ or _Smallville_, but it was a lot of fun and, overall, well-done.
I actually prefer John Haymes Newton in the first season. Gerard Christopher was probably the better actor, but Newton brought a little cocky attitude--and a unique sexiness--to the role, never seen before or since in any interpretation of Superman. It added a new dimension to the character. A good example is the Newton episode where a bad guy drew a gun on Superboy and said "Freeze!" Superboy smirked and deadpanned "Good idea!" and then encased him in a block of ice with his super-breath. I think he may have come across to some people as too much of a "bad boy" for the role, but it really did work.
The Christopher episodes were fun, but they lacked something.
Overall, the show really deserves better treatment than it has received. I hope it resurfaces somewhere soon.