I've been ruminating about this because I plan to engage the QS community for my business, but I will not do some of the things that WeGo does.
I'm creating a minimally invasive wearable device to monitor blood biochemistry. I believe I have pretty good ideas, but input from self quantifiers will help me optimize my device for users' needs and desires. This benefits everybody, and (I expect) will help identify some individuals who will be be willing and appropriate to serve as beta testers. I assume it will also get my device on the radar of some future reviewers and other thought leaders, and I feel that benefits everyone, but probably me more than others. Not all self quantifiers will want to participate, and that's fine, but if I can do a better job of creating a device that you would like to buy, I want to learn how.
What I do not intend to do is attempt to incentivize positive reviews. I feel that doing so can be OK if there is full transparency all around, but that it creates a slippery slope that is best avoided whenever possible. If I gave you free product or cash, or if I made you a paid spokesperson in exchange for a positive review, or post on social media, I feel that creates a gray area situation. With that said, I think it is OK for me to like, share, or retweet things you say publicly about my device, and to not do so if you say something negative about it. I also think it's fine for me to give away some free product, especially in promotions that are available to everybody (or at least large groups of people), or devices specifically for review (with no strings attached), or in cases of financial hardship where I believe a potential user could genuinely benefit. Unfortunately, there will always be some judgement calls.