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Adding a 2x Barlow effectively cuts the true field in half defeating the purpose of a wide field eyepiece. Adding a coma corrector especially one with zero aplification factor wont do anything for eyepieces that are not corrected to f5 or better.
A coma corrector is used to reduce the effects of primary mirror coma; it does nothing for the eyepiece. A Tele Vue Paracorr has a slight 1.15x amplifying factor which flattens the field ever so slightly for eyepieces that may exhibit field curvature in certain focal length telescopes and telescope types. The biggest advantage of the Paracorr is that it has a tuneable top which is important for visual use so that you can tweak the distance from eyepiece field stop and Paracorr for optimal correction. The Baader model appears to be more suited for photographic work but as I have not used a Baader I cannot comment further.
In any case the biggest difference you will see in any telescope especially in a relatively short Newtonian is with an eyepiece corrected down to f4. Once you look through one you will then see only primary mirror coma which at 1000mm focal length in your telescope will be quite small and most likely not objectionable. Most people say f5 is about where you start to require a coma corrector but I believe it is more of a personal preference. I can see and appreciate the difference one makes in an f6.4 telescope (1640mm focal length) although most of the time I'll view without one. I can also view quite happily without a Paracorr at f4.5 (1829mm focal length) since the Tele Vue eyepieces I use have none of the abberations present in some of the lesser corrected eyepieces I have. I mainly switch to the Paracorr if I want my Newt to come close to matching the pin point stars the TV-101 gives me across the entire field.
I do not recommend a coma corrector before getting better corrected eyepieces and therefore recommend you put the money you would spend on a coma corrector toward a highly corrected eyepiece as you will notice the difference. A not so well corrected eyepiece will show eyepiece coma and astigmatism with or without a coma corrector. Note not all eyepieces have top be highly corrected to work in your 'scope as you may find a combination that works nicely for you. However highly corrected (tested to say f4) eyepieces do work in any telescope you are ever likely to own.
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