Here is a user review of the SW 38mm eyepiece which might help
http://stargazerslounge.com/equipmen...on-review.html
He mentions some pincushion distortion and field curvature in fast newts, but really the only way to know if you are going to be satisfied with the eyepiece is to try it first. Otherwise, it might be worthwhile considering other tried and true options, such as the 35mm Panoptic. The panoptic will yield a 1.6° TFOV, (the 38mm SW yields 1.8° - so not a huge loss) with an exit pupil of 7.1mm, so it might be a worthwile option to consider. If your wallet is a bit deeper, the 31mm Naglar T5 actually yields a 1.7° TFOV with only 6.3mm exit pupil and excellent field correction which IMO would be the way to go, if funds allow.