For the aspect of copying photos, both printers provide the same copy and print resolution options and the same ink system, so there is no difference in this matter and both models provide the same results.
Be aware that borderless copying is not supported by both models, there will always borders when copying a photo on the output.
For the matter of borderless printing, the Envy Pro 6455 can print borderless photos on Photo Paper (edge-to-edge printing), the Deskjet Plus 4155 does not support borderless printing so any photo printed by the printer will have some margins around.
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