What do you like best?
The Salesforce sync remains one of the best out of all the donation processors that are affordable for most nonprofits. It allows you to pass mapped data to account, contact, opportunity, and custom questions based on SKUs (which can be unique per page, donation amount, question, etc). The recurring gift model is solid in Salesforce and you can do a decent amount of recurring gift management without ever leaving Salesforce. There are *great* features for reposting and troubleshooting if something breaks along the way from C&P to Salesforce.
The new Connect form builder is easy to use, offers decent customization features for most users' needs. If it isn't enough, a FaaS API gives developers the ability to create fancier forms. There are also integrations for Gravity Forms, Form Assembly, WooCommerce, Auctions for Salesforce, CiviCRM, and more. I haven't used enough of the crowdsource features to comment.
It has a basic virtual terminal and bulk upload features (I look forward to improvements here, but it's ok out of the box).
Support is usually responsive and helpful via several platforms (Power of Us Hub and C&P forums) and they are constantly developing new features. They have built out several things I've requested over the years, especially to improve recurring gift management.
What do you dislike?
It suffers a bit from having been around a long time with a lot of development. It's architecture, especially in Salesforce, is sprawling and it can take a while to learn it. They are working to improve documentation, but it's not always easy to find what you need. Newbies are often a bit frustrated getting up to speed. The autoresponder setup in Salesforce suffers from this problem especially and the Connect receipting isn't quite ready for all my clients have needed it to do, but it is improving!
The ability to change the recurring amount or related Salesforce campaign without cancelling and restarting a subscription would be a massive improvement for how most nonprofits manage recurring donor programs. Of the 10 or so setups I have done in C&P, this is always a wish!
The newer Connect interface looks and operates *much* nicer than the portal but often is a bit clunky for doing a lot of data work (You can't click back in most windows, update a bunch of transactions at once, etc). If you can do most of it in Salesforce, you will be better off.
Several clients have had less than stellar response rates from Sales (getting accounts set up, quotes for importing recurring gifts, etc), which is surprising given how responsive the tech support can be.
Finally, I rarely use C&P Events in Salesforce because the setup and learning curve is really large for nonprofits. It suffers from being too powerful for most of them. Staff can't easily setup events without admin help and it isn't easy to customize the experience for things like free events or addon donations. It is pretty powerful though, just more than our clients have needed.
Recommendations to others considering the product
Take full advantage of their webinars and office hours to get help and get up to speed. Work with a Partner to avoid monthly fees (transaction fees still apply).
What business problems are you solving with the product? What benefits have you realized?
All of my clients use it for most of their donation processing, online and offline. Small nonprofits are able to affordably collect donations online for the first time and larger nonprofits are getting good Salesforce integration.
(We are a partner, but the partner program only offers discounts to our customers, no kickbacks to us.)