diff --git a/benchmarks/insert.js b/benchmarks/insert.js
index effe1d5..67c3fea 100644
--- a/benchmarks/insert.js
+++ b/benchmarks/insert.js
@@ -4,16 +4,31 @@ var Datastore = require('../lib/datastore')
   , commonUtilities = require('./commonUtilities')
   , execTime = require('exec-time')
   , profiler = new execTime('INSERT BENCH')
-  , n = 10000
+  , n
   , d = new Datastore(benchDb)
+  , program = require('commander')
   ;
 
-if (process.argv[2]) { n = parseInt(process.argv[2], 10); }
+program
+  .option('-n --number [number]', 'Size of the collection to test on', parseInt)
+  .option('-i --with-index', 'Test with an index')
+  .parse(process.argv);
+
+n = program.number || 10000;
+
+console.log("----------------------------");
+console.log("Test with " + n + " documents");
+console.log(program.withIndex ? "Use an index" : "Don't use an index");
+console.log("----------------------------");
 
 async.waterfall([
   async.apply(commonUtilities.prepareDb, benchDb)
 , function (cb) {
-    d.loadDatabase(cb);
+    d.loadDatabase(function (err) {
+      if (err) { return cb(err); }
+      if (program.withIndex) { d.ensureIndex('docNumber'); }
+      cb();
+    });
   }
 , function (cb) { profiler.beginProfiling(); return cb(); }
 , async.apply(commonUtilities.insertDocs, d, n, profiler)
diff --git a/package.json b/package.json
index 490aa47..f135c1c 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,8 @@
     "mocha": "1.4.x",
     "request": "2.9.x",
     "sinon": "1.3.x",
-    "exec-time": "0.0.2"
+    "exec-time": "0.0.2",
+    "commander": "1.1.1"
   },
   "scripts": {
     "test": "make test"