Yes, the ones from bulbsthatlast4ever look well made.
I was kinda going to go that way via one of the members here having some for what was a fairly good deal at the time.
I futtered about and lost out to some one on the ebay.
Anyway, they look like decent boards and name brand components, can't tell who makes the actual led's but the rest of the components are well recognized.
If you need led lights then these are a decent choice.
Or you could build your own and spend way more and have less money but more satisfaction.
I would design around a lower voltage and regulate, that way the flasher timing and brightness would be constant at idle with the headlight on, or at speed, if I did it myself.
The bulbsthatlast4ever brake light is interesting in the way that the leds are powered. All of them are on all the time, and the brake application circumvents the running light resistance to provide higher current to the same red led's. This is clever but admittedly can cause overheating of the led's if the brake is held on for long periods. Probably not a big deal unless stuck in traffic on an uphill climb. See the installation instructions, they make note of this.
All in all, unless the words uv, ferric chloride, fr4, 1oz copper, acheson, piranha, stuffing, reflow, blah blah blah, etc are within your everyday vernacular then you should buy them from bulbsthatlast4ever. You will have more money and time on your hands vs making your own.