Which of the two functions is easier to read/understand?

gistfile1.clj

(defn interpose-non-nil-values                                                                                                                                
  "Return a string of concatenated values from the param-map in the order of keys, eliminating nil values and separating with the sep argument."              
  [sep param-map keys]                                                                                                                                        
  (apply str (interpose sep (remove nil? (map #(get param-map %) keys)))))                                                                                    
                                                                                                                                                              
(defn interpose-non-nil-values->>                                                                                                                             
  "Same as interpose-non-nil-values, but with thread-last macro. More readable?"                                                                              
  [sep param-map keys]                                                                                                                                        
  (->>                                                                                                                                                        
   (apply str)                                                                                                                                                
   (interpose sep)                                                                                                                                            
   (remove nil?)                                                                                                                                              
   (map #(get param-map %) keys))) 

I like the first one. I'm finding that having everything on one line makes it easier to read.