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ED glass in the barlow is a marketing hype. The purpose of ED glass is to reduce false colour. I used a couple of non-ED GSO barlows last w/e and looked for false colour at mid to high powers and saw none. So my advice is save a your money and get the non-ED version.
Or better, for $99 + postage you can also get the Japanese made Orion Deluxe 1.25" from Sirius Optics in QLD (well probably you can, ring them and ask), which I have no doubt is better than either GS barlow (based on my experience with the 2" Deluxe). These barlows are FMC and internally baffled which makes a lot of difference on bright objects like planets. So unless you specifically want a 2" barlow, I'd recommend the 1.25" Deluxe.
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