Like Isildur said a VPN typically will slow down your connection. Really the only time a VPN may speed up your connection is if your ISP is throttling your traffic for certain types of data (like movie streaming, etc), where the VPN masks the data types and can prevent this throttling in some cases.

However, be aware of a couple thing wrt speed: 1) If throttling is your issue-- it's possible that your ISP eventually detects you are using something goofy (i.e. VPN) and begins throttling your traffic after some use anyways, 2) there is an overhead to VPN encrypting/decrypting, so even though a ping may look faster, larger data may be slower since it has to be processed going in and coming out.

As far as the govt. now allowing ISP data mining, nothing has actually changed in this regard-- they've always had access to your data (i.e., the bill simply wasn't approved, it didn't "go away"). Still, it's probably a good idea for privacy to use a VPN I won't argue there. Furthermore I'd actually trust the ISP more than the government since an ISP has to actually compete in the market, and selling your data may be bad for their business if word got our they were selling customer data.