There is no dip in quality or effort in this film. If you enjoyed the first one and can willingly suspend disbelief when it comes to characters that come and go, you should have no problems here. Vaughn's sense of humor, understanding of visual flair and development of character is still on point here.
Burton's instincts are tempered here. He's allowed the weirdness we normally get from him, but without any of the routine "no one understands how weird I want to be" normally pushed to the forefront. Having Green in the role normally reserved for Helena Bonham Carter infests certainly helps. Ultimately we get all of the benefits of the imagination of the creators with very few of the indulgences of a director who hasn't heard "no" when it comes to a budget since Superman Lives.