I haven't used those sorts of bulbs specifically, but I would guess that flicker would be less of a problem than color quality -- they don't usually come with CRI ratings, but odds are good you're going to end up with something under 90, which is generally the bare minimum threshold for quality lighting. You might wind up with weird green or magenta casts to deal with.
I have been using ones from ikea - basically the same quality - and they work alright. The light quality isn't the best, but it definitely gets the job done. On that note, after about a year and a half of using them, I am ready to upgrade to something more professional.