I have not used any on the borrowing side, but have invested in a few companies on Wefunder and Mainvest. Mainvest went out of business because of the collapse of Silicon Valley Bank. Friends of mine were in the middle of a large (large for them) raise and it really screwed things up for them. They were able to get the deal done, but ended up having to do all the investor relations admin and logistics themselves. A huge time suck they were not prepared to take on. Just bringing that up because while it is an outlier event it could happen again and screw up a deal. More practical though is that in my experience on these platforms, it seems many use the story of what they are doing to help with fundraising. They share the story publicly to get investors. Much of the culture and practicality of search, for example, think how you have to be hush hush about a deal before its actually done, does not jive well with the crowdfunding raise model. I could see someone using it to fund a bolt-on or part of a roll-up as you could tell the story of what you are doing with your main business and be vague about the specific deal you are trying to do. Lastly, I'd put in a plug for Honeycomb Credit. They are more focused on small business than wefunder and startengine, but seem to be a reliable platform.

I used Wefunder a few years ago for a small raise of about $100k. It is purely a platform that helps with the mechanics/tactical. They do not promote or provide any investors. Just FYI. Happy to share more.