I have used it. It is a good program to use for liking a lot of posts without flagging instagram's algorithm. However, it fully depends on how you use it if you just like all of the most recent post from a hashtag, instagram may tag you. Been using it for 3 months without issues on the slow activity setting, and been limiting myself to 500 likes per day. Haven't used it for follow or unfollow (I do that on app.) I also have a friend who used it for a year without issues.
As always, Instagram's bot detection is always changing Combin is about as safe as you can get, but still is more risky than operating directly through the app. Wouldn't recommend operating the app while your liking stuff with your phone halfway across the country. If Instagram sees that your liking photos from an IP address in virginia and an ip adress in california that's a big flag.