I've had mixed luck with SainSmart, and I wouldn't go with them unless you have a lot of time to spare and can take the chance that something won't work.
I bought 4 Megas and 4 Unos from them. When I finally got around to using them all, one of the Megas and two of the Unos didn't work. But he problem is that your 90-day warranty begins with the day you place the order, so if they're on the slow boat from China like mine were, the first 30 days of your warranty period is spent shipping the product. Customer service asked me to send screen prints of the problem (can't upload sketches, and I've tried every solution such as resetting the device just before the upload begins, making sure I have the right board selected, etc.) and their response was that they were very busy and my warranty period had already expired.
When you figure the total cost for what works, three Megas and two Unos, you negate quite a bit of your savings.
I haven't had the same problem with their shields, such as the Motor Controller and Xbee shields. Those have worked fine. The only problems have been with the controllers themselves.
I bought 4 Megas and 4 Unos from them. When I finally got around to using them all, one of the Megas and two of the Unos didn't work. But he problem is that your 90-day warranty begins with the day you place the order, so if they're on the slow boat from China like mine were, the first 30 days of your warranty period is spent shipping the product. Customer service asked me to send screen prints of the problem (can't upload sketches, and I've tried every solution such as resetting the device just before the upload begins, making sure I have the right board selected, etc.) and their response was that they were very busy and my warranty period had already expired.
When you figure the total cost for what works, three Megas and two Unos, you negate quite a bit of your savings.
I haven't had the same problem with their shields, such as the Motor Controller and Xbee shields. Those have worked fine. The only problems have been with the controllers themselves.