I've not dealt with them (or heard of them), but that's not necessarily a bad thing. Every supplier was an unknown at some point. If you get no feedback about them from the folks here, why not call and have a chat with whomever is running the store to size them up. A reputable new supplier would welcome the opportunity.
They do have go prices (for the 510), especially the boxless kit for $35. Purchase their PCC separately for $25 and that's still $10 less than the $70 kit (unless that "choice of two accessories" includes two more PCCs).
That ECOjuice seems pricey, however. If I remember correctly, it's just flavored nicotined VG with some ethol maltol (which you can get cheap at Perfumer's Apprentice).
Caveat emptor and all that ... and good luck!
[I should change my signature to "Don, the Deal Finder." Of course, in this case, *you* found the deal and I just commented on I.

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