Billing software evaluation

I’m doing a new project for a customer, who wants me to write the licensing/billing module in his PHP app. So, the first thing is to decide on the billing software to use. I came up with this table (kind of a braindump thing), trying to evaluate the different solutions I found.

Updated

#	Item	PayPal	Chargify	Zuora	Plimus
1.	API
2.	Charge via API	V	V	V	V
3.	Subscription registration via API	V	V	V	V
4.	Allow changes in subscription plan/price via API	?	V	V	V
5.	Get billing information (invoices) via API	V	V	V	V
6.	Notifications	V (API)	V- (not API, but can be automatic)	V (API)	?
7.	Send invoices to customers	V	V	V	V
8.	Billing management
9.	Discounts	V	V	V
10.	Chargeback	V	V	V	V
11.	Custom workflows for issue management	X	X	V	?
12.	Prepay discounts	V- Manual
13.	Accept credit cards	V	V	V	V
14.	Environment
15.	Free test account	V	V	V	V
16.	Site stores customer payment information	V	V	V	V
17.	Integration with SF	X	X	V	X
18.	Pricing	2.9% + 0.30c per transaction	99$/month (depend on number of customers), additions for gateways	Not published	8% per transaction
19.	Customer self service portal	V	V	V	V

What do you think? Any major player I’ve left out? Anything I should add to my criteria?

Update

I’ve started with PayPal – they have terrible documentation and API. Took me a day to actually do something – but it worked. Only then I discovered that subscriptions require a PayPal account. So I’m now evaluating Zuora. I’ll post my experience with them in future posts.