I just had my car tuned by Jan of Revolution Mini Works yesterday and man-o-man is it awesome. Amazing how much better it drives. I haven't had the annoying rough start and it didn't stumble while idling with the a/c on after the tune. It pulls strong through the whole rpm range. I was surprised how much I gained with a tune! I highly recommend having him tune your mini. I had a intake, one-ball, pulley, and plugs installed a few months ago and it didn't seem to make much of a difference but WOW did Jan wake those mod's up. Did I forget to mention the B@d@ss red GT3 that he had done just prior? He can work his magic on anything.
Just do it!