attachment_fu slows down update

Hi,

I use attachment_fu and it slows down update.

[Models]
product has many pictures.

[Update]
product.update_attributes("pictures_attributes"=>{
"6"=>{"_delete"=>"0", "color_id"=>"3", "id"=>"2953"},
"11"=>{"_delete"=>"0", "color_id"=>"9", "id"=>"2921"},
"22"=>{"_delete"=>"0", "color_id"=>"24", "id"=>"2977"},
"7"=>{"_delete"=>"0", "color_id"=>"4", "id"=>"2965"},
"12"=>{"_delete"=>"0", "color_id"=>"10", "id"=>"2949"},
"23"=>{"_delete"=>"0", "color_id"=>"27", "id"=>"2969"},
"8"=>{"_delete"=>"0", "color_id"=>"5", "id"=>"2917"},
"13"=>{"_delete"=>"0", "color_id"=>"11", "id"=>"2913"},
"24"=>{"_delete"=>"0", "color_id"=>"28", "id"=>"2985"},
"9"=>{"_delete"=>"0", "color_id"=>"7", "id"=>"2989"},
"14"=>{"_deete"=>"0", "color_id"=>"12", "id"=>"2973"},
"25"=>{"_delete"=>"0", "color_id"=>"77", "id"=>"2997"},
"15"=>{"_delete"=>"0", "color_id"=>"13", "id"=>"2925"},
"0"=>{"_delete"=>"0", "color_id"=>"", "id"=>"2937"},
"16"=>{"_delete"=>"0", "color_id"=>"14", "id"=>"2941"},
"1"=>{"_delete"=>"0", "color_id"=>"", "id"=>"2981"},
"17"=>{"_delete"=>"0", "color_id"=>"14", "id"=>"1897"},
"2"=>{"_delete"=>"0", "color_id"=>"", "id"=>"2961"},
"18"=>{"_delete"=>"0", "color_id"=>"16", "id"=>"2929"},
"3"=>{"_delete"=>"0", "colo_id"=>"2", "id"=>"2909"},
"19"=>{"_delete"=>"0", "color_id"=>"17", "id"=>"2945"},
"20"=>{"_delete"=>"0", "color_id"=>"18", "id"=>"2957"},
"4"=>{"_delete"=>"0", "color_id"=>"2", "id"=>"1893"},
"10"=>{"_delete"=>"0", "color_id"=>"8", "id"=>"2993"},
"21"=>{"_delete"=>"0", "color_id"=>"21", "id"=>"2933"},
"5"=>{"_delete"=>"0", "color_id"=>"3", "id"=>"1901"}
})

This takes 15 seconds.

The workaround I found is
product.attributes = "pictures_attributes"=>{
"6"=>{"_delete"=>"0", "color_id"=>"3", "id"=>"2953"},
"11"=>{"_delete"=>"0", "color_id"=>"9", "id"=>"2921"},
"22"=>{"_delete"=>"0", "color_id"=>"24", "id"=>"2977"},
"7"=>{"_delete"=>"0", "color_id"=>"4", "id"=>"2965"},
"12"=>{"_delete"=>"0", "color_id"=>"10", "id"=>"2949"},
"23"=>{"_delete"=>"0", "color_id"=>"27", "id"=>"2969"},
"8"=>{"_delete"=>"0", "color_id"=>"5", "id"=>"2917"},
"13"=>{"_delete"=>"0", "color_id"=>"11", "id"=>"2913"},
"24"=>{"_delete"=>"0", "color_id"=>"28", "id"=>"2985"},
"9"=>{"_delete"=>"0", "color_id"=>"7", "id"=>"2989"},
"14"=>{"_deete"=>"0", "color_id"=>"12", "id"=>"2973"},
"25"=>{"_delete"=>"0", "color_id"=>"77", "id"=>"2997"},
"15"=>{"_delete"=>"0", "color_id"=>"13", "id"=>"2925"},
"0"=>{"_delete"=>"0", "color_id"=>"", "id"=>"2937"},
"16"=>{"_delete"=>"0", "color_id"=>"14", "id"=>"2941"},
"1"=>{"_delete"=>"0", "color_id"=>"", "id"=>"2981"},
"17"=>{"_delete"=>"0", "color_id"=>"14", "id"=>"1897"},
"2"=>{"_delete"=>"0", "color_id"=>"", "id"=>"2961"},
"18"=>{"_delete"=>"0", "color_id"=>"16", "id"=>"2929"},
"3"=>{"_delete"=>"0", "colo_id"=>"2", "id"=>"2909"},
"19"=>{"_delete"=>"0", "color_id"=>"17", "id"=>"2945"},
"20"=>{"_delete"=>"0", "color_id"=>"18", "id"=>"2957"},
"4"=>{"_delete"=>"0", "color_id"=>"2", "id"=>"1893"},
"10"=>{"_delete"=>"0", "color_id"=>"8", "id"=>"2993"},
"21"=>{"_delete"=>"0", "color_id"=>"21", "id"=>"2933"},
"5"=>{"_delete"=>"0", "color_id"=>"3", "id"=>"1901"}
})
product.save false

This is fast but I am not sure this is the right way.
Is there a better way?

Thanks.

Sam