Boy did i have doubts about this. The trailers certainly made me more optimistic, but I still put off watching the first episode when it came out because i really didn't know what to expect.
Of course its over the top (it is lethal weapon after all) but here's the thing... Right now i'm looking forward to this show every week more than any other. They've completely nailed the casting and characters of Riggs and Murtaugh, from Murtaugh's protectiveness of his family to Riggs's crazy outward charm, thinly veiling a near suicidal depression. More than that though, they've managed to recreate the bromance that made the originals so memorable. That is truly where this show excels, at being a damn good buddy cop story.
So here's my suggestion. Don't expect anything, don't pre-judge it, just watch the first few episodes. If you still don't like it then fine, but i'm betting that if you liked the originals, then you will.