If you can't spend up into one of the higher end JL amps just go with the Sundown. The higher end JL amps are very solid, will hold good resale value, should give you decades of service life, and the 1000-1200W units will be a good match for a single W7.
SFB is a solid value and you can at least expect the 2 year warranty out of them. I wouldn't expect a whole lot of resale value on those though as even MSRP is dropping already on the first generation and it has only been like half a year since they're on the market.