It is important to inform other potential buyers of any "issues" they had with a buyer.
Keep in mind no seller is going to have 100% positive all the time. Think of how many Best buys, futureshops, etc have perfectly satisfied customers all the time. Impossible, I'm sure they have at least one dissatisfied customer every few hours. So this one incident would not keep me from buying from shootsoft with confidence.
From the facts:
Drache Received wrong item (unclear if Drache was told by Shootsoft what method they want the gun shipped back by before he sent it back).
Paid for express shipping and was not given express shipping.
I'll have to side with Drache.
In an effort to learn from this,
Shootsoft needs to inform buyers how they want their item shipped back to them, and who should pay for this cost. This needs to be clearly written as part of the buying contract on the website before the user buys a gun. This would help avoid or decrease the chance of dissatisfied customer.
Drache, it might have been better to have created a thread but not used Shootsoft named until much later in the thread and/or after mods asked for it to resolve dispute.
One last thing in general (I learned the hard way), always try to communicate professionally and politely during business, because your words might just show up on a forum thread and make you look bad.