I had one for a few months, and those fretboards are pretty good. Get a radiused sanding block from stewmac.com and some sand paper, and you can smooth your fretless fingerboard any time you need to. It's pretty easy and fun. But they hold better than what you think.
I have had a cheap Yamaha fretless with rounds for 7 years, and just recently did the sanding myself. Very nice, and easy, and fun.
In any case, if you happen to have no skills to even do a sanding, just burn that SX in the winter time and get another one. For those prices, might as well.
They sound pretty good out of the box. The only thing that bothered me was that the pickups' screws will strip even with the lightest adjustment, and the pickups happened to be pretty hot, so I wanted to lower them -- and I couldn't. It would be a good idea to get new screws.
And it was a bit too heavy (not too bad, but maybe a little over 9 lbs). Other than that, great fretless.
BTW, I really like Sadowsky light-gauge flatwound strings on a fretless. They are very bright and the "mwah" like crazy, yet they give the nice thump and smoothness of a flat. Not cheap, but they will last a few years.