I guess it will depend mostly on how much you are willing to spend. An LSI 9207 8i (they do not make a 4 port variant as far as I know) will utilize PCIe 3 lanes, while an LSI 9211 4i (or 8i) will only use PCIe 2 lanes but cost a little less. Lastly, a 9300 4i will give you 12gb speed instead of 6gb (more so for if you upgrade in the future). Both Areca and Adaptec make similar products but you would have an issue finding them new (these are all older cards) whereas the LSI cards are still sold by retailers like newegg.
I suppose I should add you can find cheap Syba cards and the like but I would avoid them entirely as they tend to suck.