Malt names get very confusing!

Whilst I'm sure either one will be fine, it's important to know what recipe you are brewing and what percentage of brown malt is in it and what the style wants to acheive.

I've never used brown malt so I'm in the same position as you. My first step though would be to Google for descriptions on the two malts to see if there are any obvious differences. Unfortunately, getting good descriptions, even from the maltsters themselves, can be very hard. I just had a quick Google and couldn't find anything comprehensive. With more time, you will do much better I'm sure.

I couldn't even find the Gold Swaen Maltster site. Best description I got after a minute or two weas from midbrewsupply.com...

"GoldSwaen Brown Malt intensifies the beer's body and its smoothness, promotes head formation and retention. Caramel malts are produced in several color stages. They make a considerable contribution to the malt aroma, the full taste and color, and to the head retention. By the special production procedure this malt has a dark bronze shine and a typical aroma which serves to intensify and stabilize flavor. GoldSwaen Brown Malt has intense caramel & biscuit aroma, round body and color."

On the Crisp Maltster site, they had about two sentences. On bsgcraftbrewing I found this, "William Crisp Brown Malt is roasted specialty malt. It has a strong, dark-toasted grain flavor, slightly nutty with a hint of bitter chocolate. Brown malt imparts dark amber to light brown hues. It is used in many older English ale styles, and is an essential ingredient for traditional porters."

So, for me at least, I think my second paragraph in this post becomes more relevant as that might let you know which of the two will be best. Post those details as there could be someone here who knows about brown malts.

They certainly don't make it easy .