Abysmal customer service
Abysmal customer service, payment processor that doesn't work. They will make you email FastSpring (this bit is just unbelievable to be honest), if you're at this stage, don't waste time. It doesn't get better. After 2 days of drama, calling my bank, emailing FastSpring. I came to realise that it doesn't matter if their core product is good because if you need to speak to someone, they're not helpful. Imagine if you have to get a refund or something. Stick with semrush or whatever other provider you can find if you want to get the job done.