Here in Eretz Israel we've already read Parshas Shelach, but elsewhere it's this coming Shabbos. I told our tzitzit tie-ers to keep their schedule available next week, because we typically have a heavy load of orders after Parshas Shelach, which ends with the commandment of tzitzit (starting at verse 37 here).
Every year the Ptil Tekhelet Association has a big sale in honor of Parshat Shelach. One of the workers here asked if we would do some sort of Ptil Tekhelet promotion as well. I said I'd take a look at their sale and then consider it.
Their sale is quite tempting. You pay for the strings, and get the beged (tallit katan garment) free. To be more accurate, it's free if you go with cotton, or $12 more if you want wool. That's quite a bargain, and there's no way we can compete with it.
Note that to really compare the bottom-line figure, you have to check how much the shipping fee comes out to. I think our shipping fee might be lower, but I haven't gotten around to checking that.
But then I took a look at their regular, year-round prices, and discovered that our prices are competitive, even though they focus exclusively on techeiles, while we offer a lot more.
So if you're willing to trust me to offer my two cents in a matter in which I have a vested interest, I would advise prospective buyers as follows: If the Parshat Shelach sale is still going and you find the type of tallit katan garment you want (they have a limited selection) and you're not in a big rush (there's a note on their site saying it could take 60 days to get it tied), place an order on the Ptil Tekhelet store.
For $10 off any tallit katan order with techelet strings, use coupon code TKHL5SHLCH during checkout. Valid for one week after Parshat Shelach 5782.