He's certainly approachable for hassle-free below-market prices, but I don't see the need in this particular case to squeeze/antagonize a small business vendor for an even lower price on an already-solid deal, especially when it's so clearly specified in the terms that promo codes don't apply to these. He updates those terms regularly to send a clear message - couldn't be any clearer here, IMO.
Open-Box or B-stock hfm planars are just as good as new after a couple swipes with a surface wipe. HE-400 for $245 w/ Velours & Free Priority Shipping is already effectively over 20% off of the recently-reduced price... If anybody's interested in those, just take the deal & send him your thanks. No need to go around lowballing good people.