Travelling early June, looking at 15 day Swiss travel pass, is there any advantage or disadvantage to purchasing the Pass from home or waiting until we arrive in Zurich. In addition, the home Pass is a printout do we convert that to a card or something in Zurich? Thanks
No advantage or disadvantage. If you buy in advance from the SBB site, that will be exactly the same price as you would pay at a Swiss border or airport station.
Prices and purchase on the SBB site here: https://www.sbb.ch/en/leisure-holidays/travel-in-switzerland/international-guests/swiss-travel-pass.html
If you buy from a reseller with prices in a foreign currency, that may cost more.
If you buy online you get a PDF file which you have to print out. This is your ticket, you do not have to convert it. Show this printout and your passport to the ticket inspector on the train whenever asked for. The ticket has a name on it (which you enter when you buy), and the ID check stops you making two copies and two different people using it (unless there are two people called "Valleyguy").
The price on this website is $525. The SBB price is 485 CHF, which converts to around $506. But to that you must add whatever foreign transaction fee your credit card charges, if any. If that fee is 4% the price comes out the same.